src/FDM/JSBSim/FGAircraft.cpp

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Module:       FGAircraft.cpp
   4  Author:       Jon S. Berndt
   5  Date started: 12/12/98
   6  Purpose:      Encapsulates an aircraft
   7  Called by:    FGFDMExec
   8
   9  ------------- Copyright (C) 1999  Jon S. Berndt (jsb@hal-pc.org) -------------
  10
  11  This program is free software; you can redistribute it and/or modify it under
  12  the terms of the GNU 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 General Public License for more
  19  details.
  20
  21  You should have received a copy of the GNU 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 General Public License can also be found on
  26  the world wide web at http://www.gnu.org.
  27
  28 FUNCTIONAL DESCRIPTION
  29 --------------------------------------------------------------------------------
  30 Models the aircraft reactions and forces. This class is instantiated by the
  31 FGFDMExec class and scheduled as an FDM entry.
  32
  33 HISTORY
  34 --------------------------------------------------------------------------------
  35 12/12/98   JSB   Created
  36 04/03/99   JSB   Changed Aero() method to correct body axis force calculation
  37                  from wind vector. Fix provided by Tony Peden.
  38 05/03/99   JSB   Changed (for the better?) the way configurations are read in.
  39 9/17/99     TP   Combined force and moment functions. Added aero reference
  40                  point to config file. Added calculations for moments due to
  41                  difference in cg and aero reference point
  42
  43 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  44 COMMENTS, REFERENCES,  and NOTES
  45 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  46
  47 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  48 INCLUDES
  49 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  50
  51 #include <sys/stat.h>
  52 #include <sys/types.h>
  53
  54 #ifdef FGFS
  55 #  ifndef __BORLANDC__
  56 #    include <simgear/compiler.h>
  57 #  endif
  58 #  ifdef SG_HAVE_STD_INCLUDES
  59 #    include <cmath>
  60 #  else
  61 #    include <math.h>
  62 #  endif
  63 #else
  64 #  if defined (sgi) && !defined(__GNUC__)
  65 #    include <math.h>
  66 #  else
  67 #    include <cmath>
  68 #  endif
  69 #endif
  70
  71 #include "FGAircraft.h"
  72 #include "FGMassBalance.h"
  73 #include "FGInertial.h"
  74 #include "FGGroundReactions.h"
  75 #include "FGAerodynamics.h"
  76 #include "FGTranslation.h"
  77 #include "FGRotation.h"
  78 #include "FGAtmosphere.h"
  79 #include "FGState.h"
  80 #include "FGFDMExec.h"
  81 #include "FGFCS.h"
  82 #include "FGPosition.h"
  83 #include "FGAuxiliary.h"
  84 #include "FGOutput.h"
  85 #include "FGPropertyManager.h"
  86
  87 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  88 DEFINITIONS
  89 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  90
  91 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  92 GLOBAL DATA
  93 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  94
  95 static const char *IdSrc = "$Id$";
  96 static const char *IdHdr = ID_AIRCRAFT;
  97
  98 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  99 CLASS IMPLEMENTATION
 100 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
 101
 102 FGAircraft::FGAircraft(FGFDMExec* fdmex) : FGModel(fdmex)
 103 {
 104   Name = "FGAircraft";
 105   WingIncidence   = 0.0;
 106   impending_stall = 0.0;
 107   alphaclmin = alphaclmax = 0.0;
 108   HTailArea = VTailArea = 0.0;
 109   HTailArm  = VTailArm  = 0.0;
 110   lbarh = lbarv = 0.0;
 111   vbarh = vbarv = 0.0;
 112   bi2vel = ci2vel = 0.0;
 113   alphaw = 0.0;
 114
 115   bind();
 116
 117   Debug(0);
 118 }
 119
 120 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 121
 122 FGAircraft::~FGAircraft()
 123 {
 124   unbind();
 125   Debug(1);
 126 }
 127
 128 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 129
 130 bool FGAircraft::Run(void)
 131 {
 132   double twovel;
 133
 134   if (!FGModel::Run()) {                 // if false then execute this Run()
 135     vForces.InitMatrix();
 136     vForces += Aerodynamics->GetForces();
 137     vForces += Inertial->GetForces();
 138     vForces += Propulsion->GetForces();
 139     vForces += GroundReactions->GetForces();
 140
 141     vMoments.InitMatrix();
 142     vMoments += Aerodynamics->GetMoments();
 143     vMoments += Propulsion->GetMoments();
 144     vMoments += GroundReactions->GetMoments();
 145
 146     vBodyAccel = vForces/MassBalance->GetMass();
 147
 148     vNcg = vBodyAccel/Inertial->gravity();
 149
 150     vNwcg = State->GetTb2s() * vNcg;
 151     vNwcg(3) = -1*vNwcg(3) + 1;
 152
 153     twovel = 2*Translation->GetVt();
 154     if (twovel > 0) {
 155       bi2vel = WingSpan / twovel;
 156       ci2vel = cbar / twovel;
 157     }
 158
 159     alphaw = Translation->Getalpha() + WingIncidence;
 160
 161     if (alphaclmax != 0) {
 162       if (Translation->Getalpha() > 0.85*alphaclmax) {
 163         impending_stall = 10*(Translation->Getalpha()/alphaclmax - 0.85);
 164       } else {
 165         impending_stall = 0;
 166       }
 167     }
 168
 169     return false;
 170   } else {                               // skip Run() execution this time
 171     return true;
 172   }
 173 }
 174
 175 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 176
 177 float FGAircraft::GetNlf(void)
 178 {
 179   return -1*Aerodynamics->GetvFs(3)/MassBalance->GetWeight();
 180 }
 181
 182 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 183
 184 bool FGAircraft::Load(FGConfigFile* AC_cfg)
 185 {
 186   string token = "";
 187   string parameter;
 188   double EW, bixx, biyy, bizz, bixy, bixz;
 189   double pmWt, pmX, pmY, pmZ;
 190   FGColumnVector3 vbaseXYZcg;
 191
 192   AC_cfg->GetNextConfigLine();
 193
 194   while ((token = AC_cfg->GetValue()) != string("/METRICS")) {
 195     *AC_cfg >> parameter;
 196     if (parameter == "AC_WINGAREA") {
 197       *AC_cfg >> WingArea;
 198       if (debug_lvl > 0) cout << "    WingArea: " << WingArea  << endl;
 199     } else if (parameter == "AC_WINGSPAN") {
 200       *AC_cfg >> WingSpan;
 201       if (debug_lvl > 0) cout << "    WingSpan: " << WingSpan  << endl;
 202     } else if (parameter == "AC_WINGINCIDENCE") {
 203       *AC_cfg >> WingIncidence;
 204       if (debug_lvl > 0) cout << "    Chord: " << cbar << endl;
 205     } else if (parameter == "AC_CHORD") {
 206       *AC_cfg >> cbar;
 207       if (debug_lvl > 0) cout << "    Chord: " << cbar << endl;
 208     } else if (parameter == "AC_HTAILAREA") {
 209       *AC_cfg >> HTailArea;
 210       if (debug_lvl > 0) cout << "    H. Tail Area: " << HTailArea << endl;
 211     } else if (parameter == "AC_HTAILARM") {
 212       *AC_cfg >> HTailArm;
 213       if (debug_lvl > 0) cout << "    H. Tail Arm: " << HTailArm << endl;
 214     } else if (parameter == "AC_VTAILAREA") {
 215       *AC_cfg >> VTailArea;
 216       if (debug_lvl > 0) cout << "    V. Tail Area: " << VTailArea << endl;
 217     } else if (parameter == "AC_VTAILARM") {
 218       *AC_cfg >> VTailArm;
 219       if (debug_lvl > 0) cout << "    V. Tail Arm: " << VTailArm << endl;
 220     } else if (parameter == "AC_IXX") {
 221       *AC_cfg >> bixx;
 222       if (debug_lvl > 0) cout << "    baseIxx: " << bixx << endl;
 223       MassBalance->SetBaseIxx(bixx);
 224     } else if (parameter == "AC_IYY") {
 225       *AC_cfg >> biyy;
 226       if (debug_lvl > 0) cout << "    baseIyy: " << biyy << endl;
 227       MassBalance->SetBaseIyy(biyy);
 228     } else if (parameter == "AC_IZZ") {
 229       *AC_cfg >> bizz;
 230       if (debug_lvl > 0) cout << "    baseIzz: " << bizz << endl;
 231       MassBalance->SetBaseIzz(bizz);
 232     } else if (parameter == "AC_IXY") {
 233       *AC_cfg >> bixy;
 234       if (debug_lvl > 0) cout << "    baseIxy: " << bixy  << endl;
 235       MassBalance->SetBaseIxy(bixy);
 236     } else if (parameter == "AC_IXZ") {
 237       *AC_cfg >> bixz;
 238       if (debug_lvl > 0) cout << "    baseIxz: " << bixz  << endl;
 239       MassBalance->SetBaseIxz(bixz);
 240     } else if (parameter == "AC_EMPTYWT") {
 241       *AC_cfg >> EW;
 242       MassBalance->SetEmptyWeight(EW);
 243       if (debug_lvl > 0) cout << "    EmptyWeight: " << EW  << endl;
 244     } else if (parameter == "AC_CGLOC") {
 245       *AC_cfg >> vbaseXYZcg(eX) >> vbaseXYZcg(eY) >> vbaseXYZcg(eZ);
 246       MassBalance->SetBaseCG(vbaseXYZcg);
 247       if (debug_lvl > 0) cout << "    CG (x, y, z): " << vbaseXYZcg << endl;
 248     } else if (parameter == "AC_EYEPTLOC") {
 249       *AC_cfg >> vXYZep(eX) >> vXYZep(eY) >> vXYZep(eZ);
 250       if (debug_lvl > 0) cout << "    Eyepoint (x, y, z): " << vXYZep << endl;
 251     } else if (parameter == "AC_AERORP") {
 252       *AC_cfg >> vXYZrp(eX) >> vXYZrp(eY) >> vXYZrp(eZ);
 253       if (debug_lvl > 0) cout << "    Ref Pt (x, y, z): " << vXYZrp << endl;
 254     } else if (parameter == "AC_ALPHALIMITS") {
 255       *AC_cfg >> alphaclmin >> alphaclmax;
 256       if (debug_lvl > 0) cout << "    Maximum Alpha: " << alphaclmax
 257              << "    Minimum Alpha: " << alphaclmin
 258              << endl;
 259     } else if (parameter == "AC_POINTMASS") {
 260       *AC_cfg >> pmWt >> pmX >> pmY >> pmZ;
 261       MassBalance->AddPointMass(pmWt, pmX, pmY, pmZ);
 262       if (debug_lvl > 0) cout << "    Point Mass Object: " << pmWt << " lbs. at "
 263                          << "X, Y, Z (in.): " << pmX << "  " << pmY << "  " << pmZ
 264                          << endl;
 265     }
 266   }
 267
 268   // calculate some derived parameters
 269   if (cbar != 0.0) {
 270     lbarh = HTailArm/cbar;
 271     lbarv = VTailArm/cbar;
 272     if (WingArea != 0.0) {
 273       vbarh = HTailArm*HTailArea / (cbar*WingArea);
 274       vbarv = VTailArm*VTailArea / (cbar*WingArea);
 275     }
 276   }
 277   return true;
 278 }
 279
 280 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 281
 282 void FGAircraft::bind(void)
 283 {
 284   PropertyManager->Tie("metrics/Sw-sqft", this,
 285                        &FGAircraft::GetWingArea);
 286   PropertyManager->Tie("metrics/bw-ft", this,
 287                        &FGAircraft::GetWingSpan);
 288   PropertyManager->Tie("metrics/cbarw-ft", this,
 289                        &FGAircraft::Getcbar);
 290   PropertyManager->Tie("metrics/iw-deg", this,
 291                        &FGAircraft::GetWingIncidence);
 292   PropertyManager->Tie("metrics/Sh-sqft", this,
 293                        &FGAircraft::GetHTailArea);
 294   PropertyManager->Tie("metrics/lh-ft", this,
 295                        &FGAircraft::GetHTailArm);
 296   PropertyManager->Tie("metrics/Sv-sqft", this,
 297                        &FGAircraft::GetVTailArea);
 298   PropertyManager->Tie("metrics/lv-ft", this,
 299                        &FGAircraft::GetVTailArm);
 300   PropertyManager->Tie("metrics/lh-norm", this,
 301                        &FGAircraft::Getlbarh);
 302   PropertyManager->Tie("metrics/lv-norm", this,
 303                        &FGAircraft::Getlbarv);
 304   PropertyManager->Tie("metrics/vbarh-norm", this,
 305                        &FGAircraft::Getvbarh);
 306   PropertyManager->Tie("metrics/vbarv-norm", this,
 307                        &FGAircraft::Getvbarv);
 308   PropertyManager->Tie("moments/l-total-lbsft", this,1,
 309                        &FGAircraft::GetMoments);
 310   PropertyManager->Tie("moments/m-total-lbsft", this,2,
 311                        &FGAircraft::GetMoments);
 312   PropertyManager->Tie("moments/n-total-lbsft", this,3,
 313                        &FGAircraft::GetMoments);
 314   PropertyManager->Tie("forces/fbx-total-lbs", this,1,
 315                        &FGAircraft::GetForces);
 316   PropertyManager->Tie("forces/fby-total-lbs", this,2,
 317                        &FGAircraft::GetForces);
 318   PropertyManager->Tie("forces/fbz-total-lbs", this,3,
 319                        &FGAircraft::GetForces);
 320   PropertyManager->Tie("metrics/aero-rp-x-ft", this,1,
 321                        &FGAircraft::GetXYZrp);
 322   PropertyManager->Tie("metrics/aero-rp-y-ft", this,2,
 323                        &FGAircraft::GetXYZrp);
 324   PropertyManager->Tie("metrics/aero-rp-z-ft", this,3,
 325                        &FGAircraft::GetXYZrp);
 326   PropertyManager->Tie("metrics/eyepoint-x-ft", this,1,
 327                        &FGAircraft::GetXYZep);
 328   PropertyManager->Tie("metrics/eyepoint-y-ft", this,2,
 329                        &FGAircraft::GetXYZep);
 330   PropertyManager->Tie("metrics/eyepoint-z-ft", this,3,
 331                        &FGAircraft::GetXYZep);
 332   PropertyManager->Tie("metrics/alpha-max-deg", this,
 333                        &FGAircraft::GetAlphaCLMax,
 334                        &FGAircraft::SetAlphaCLMax,
 335                        true);
 336   PropertyManager->Tie("metrics/alpha-min-deg", this,
 337                        &FGAircraft::GetAlphaCLMin,
 338                        &FGAircraft::SetAlphaCLMin,
 339                        true);
 340   PropertyManager->Tie("aero/bi2vel", this,
 341                        &FGAircraft::GetBI2Vel);
 342   PropertyManager->Tie("aero/ci2vel", this,
 343                        &FGAircraft::GetCI2Vel);
 344   PropertyManager->Tie("aero/alpha-wing-rad", this,
 345                        &FGAircraft::GetAlphaW);
 346   PropertyManager->Tie("systems/stall-warn-norm", this,
 347                         &FGAircraft::GetStallWarn);
 348 }
 349
 350 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 351
 352 void FGAircraft::unbind(void)
 353 {
 354   PropertyManager->Untie("metrics/Sw-sqft");
 355   PropertyManager->Untie("metrics/bw-ft");
 356   PropertyManager->Untie("metrics/cbarw-ft");
 357   PropertyManager->Untie("metrics/iw-deg");
 358   PropertyManager->Untie("metrics/Sh-sqft");
 359   PropertyManager->Untie("metrics/lh-ft");
 360   PropertyManager->Untie("metrics/Sv-sqft");
 361   PropertyManager->Untie("metrics/lv-ft");
 362   PropertyManager->Untie("metrics/lh-norm");
 363   PropertyManager->Untie("metrics/lv-norm");
 364   PropertyManager->Untie("metrics/vbarh-norm");
 365   PropertyManager->Untie("metrics/vbarv-norm");
 366   PropertyManager->Untie("moments/l-total-lbsft");
 367   PropertyManager->Untie("moments/m-total-lbsft");
 368   PropertyManager->Untie("moments/n-total-lbsft");
 369   PropertyManager->Untie("forces/fbx-total-lbs");
 370   PropertyManager->Untie("forces/fby-total-lbs");
 371   PropertyManager->Untie("forces/fbz-total-lbs");
 372   PropertyManager->Untie("metrics/aero-rp-x-ft");
 373   PropertyManager->Untie("metrics/aero-rp-y-ft");
 374   PropertyManager->Untie("metrics/aero-rp-z-ft");
 375   PropertyManager->Untie("metrics/eyepoint-x-ft");
 376   PropertyManager->Untie("metrics/eyepoint-y-ft");
 377   PropertyManager->Untie("metrics/eyepoint-z-ft");
 378   PropertyManager->Untie("metrics/alpha-max-deg");
 379   PropertyManager->Untie("metrics/alpha-min-deg");
 380   PropertyManager->Untie("aero/bi2vel");
 381   PropertyManager->Untie("aero/ci2vel");
 382   PropertyManager->Untie("aero/alpha-wing-rad");
 383   PropertyManager->Untie("systems/stall-warn-norm");
 384 }
 385
 386 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 387 //    The bitmasked value choices are as follows:
 388 //    unset: In this case (the default) JSBSim would only print
 389 //       out the normally expected messages, essentially echoing
 390 //       the config files as they are read. If the environment
 391 //       variable is not set, debug_lvl is set to 1 internally
 392 //    0: This requests JSBSim not to output any messages
 393 //       whatsoever.
 394 //    1: This value explicity requests the normal JSBSim
 395 //       startup messages
 396 //    2: This value asks for a message to be printed out when
 397 //       a class is instantiated
 398 //    4: When this value is set, a message is displayed when a
 399 //       FGModel object executes its Run() method
 400 //    8: When this value is set, various runtime state variables
 401 //       are printed out periodically
 402 //    16: When set various parameters are sanity checked and
 403 //       a message is printed out when they go out of bounds
 404
 405 void FGAircraft::Debug(int from)
 406 {
 407   if (debug_lvl <= 0) return;
 408
 409   if (debug_lvl & 1) { // Standard console startup message output
 410     if (from == 0) { // Constructor
 411     }
 412   }
 413   if (debug_lvl & 2 ) { // Instantiation/Destruction notification
 414     if (from == 0) cout << "Instantiated: FGAircraft" << endl;
 415     if (from == 1) cout << "Destroyed:    FGAircraft" << endl;
 416   }
 417   if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
 418   }
 419   if (debug_lvl & 8 ) { // Runtime state variables
 420   }
 421   if (debug_lvl & 16) { // Sanity checking
 422   }
 423   if (debug_lvl & 64) {
 424     if (from == 0) { // Constructor
 425       cout << IdSrc << endl;
 426       cout << IdHdr << endl;
 427     }
 428   }
 429 }
 430