src/FDM/JSBSim/models/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 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 Models the aircraft reactions and forces. This class is instantiated by the
  31 FGFDMExec class and scheduled as an FDM entry.
  32
  33 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  34 COMMENTS, REFERENCES,  and NOTES
  35 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  36
  37 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  38 INCLUDES
  39 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  40
  41 #include <sys/stat.h>
  42 #include <sys/types.h>
  43
  44 #ifdef FGFS
  45 #  ifndef __BORLANDC__
  46 #    include <simgear/compiler.h>
  47 #  endif
  48 #  ifdef SG_HAVE_STD_INCLUDES
  49 #    include <cmath>
  50 #  else
  51 #    include <math.h>
  52 #  endif
  53 #else
  54 #  if defined (sgi) && !defined(__GNUC__)
  55 #    include <math.h>
  56 #  else
  57 #    include <cmath>
  58 #  endif
  59 #endif
  60
  61 #include "FGAircraft.h"
  62 #include "FGMassBalance.h"
  63 #include "FGInertial.h"
  64 #include "FGGroundReactions.h"
  65 #include "FGAerodynamics.h"
  66 #include <FGState.h>
  67 #include <FGFDMExec.h>
  68 #include "FGPropagate.h"
  69 #include <input_output/FGPropertyManager.h>
  70
  71 namespace JSBSim {
  72
  73 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  74 DEFINITIONS
  75 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  76
  77 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  78 GLOBAL DATA
  79 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  80
  81 static const char *IdSrc = "$Id$";
  82 static const char *IdHdr = ID_AIRCRAFT;
  83
  84 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  85 CLASS IMPLEMENTATION
  86 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  87
  88 FGAircraft::FGAircraft(FGFDMExec* fdmex) : FGModel(fdmex)
  89 {
  90   Name = "FGAircraft";
  91   WingSpan = 0.0;
  92   HTailArea = VTailArea = 0.0;
  93   HTailArm  = VTailArm  = 0.0;
  94   lbarh = lbarv = 0.0;
  95   vbarh = vbarv = 0.0;
  96   WingIncidence = 0.0;
  97   HoldDown = 0;
  98
  99   bind();
 100
 101   Debug(0);
 102 }
 103
 104 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 105
 106 FGAircraft::~FGAircraft()
 107 {
 108   unbind();
 109   Debug(1);
 110 }
 111
 112 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 113
 114 bool FGAircraft::Run(void)
 115 {
 116   if (FGModel::Run()) return true;
 117   if (FDMExec->Holding()) return false;
 118
 119   vForces.InitMatrix();
 120   if (!HoldDown) {
 121     vForces += Aerodynamics->GetForces();
 122     vForces += Propulsion->GetForces();
 123     vForces += GroundReactions->GetForces();
 124   }
 125
 126   vMoments.InitMatrix();
 127   if (!HoldDown) {
 128     vMoments += Aerodynamics->GetMoments();
 129     vMoments += Propulsion->GetMoments();
 130     vMoments += GroundReactions->GetMoments();
 131   }
 132
 133   vBodyAccel = vForces/MassBalance->GetMass();
 134
 135   vNcg = vBodyAccel/Inertial->gravity();
 136
 137   vNwcg = State->GetTb2s() * vNcg;
 138   vNwcg(3) = -1*vNwcg(3) + 1;
 139
 140   return false;
 141 }
 142
 143 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 144
 145 double FGAircraft::GetNlf(void)
 146 {
 147   return -1*Aerodynamics->GetvFs(3)/MassBalance->GetWeight();
 148 }
 149
 150 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 151
 152 bool FGAircraft::Load(Element* el)
 153 {
 154   string element_name;
 155   Element* element;
 156
 157   if (el->FindElement("wingarea"))
 158     WingArea = el->FindElementValueAsNumberConvertTo("wingarea", "FT2");
 159   if (el->FindElement("wingspan"))
 160     WingSpan = el->FindElementValueAsNumberConvertTo("wingspan", "FT");
 161   if (el->FindElement("chord"))
 162     cbar = el->FindElementValueAsNumberConvertTo("chord", "FT");
 163   if (el->FindElement("wing_incidence"))
 164     WingIncidence = el->FindElementValueAsNumberConvertTo("wing_incidence", "DEG");
 165   if (el->FindElement("htailarea"))
 166     HTailArea = el->FindElementValueAsNumberConvertTo("htailarea", "FT2");
 167   if (el->FindElement("htailarm"))
 168     HTailArm = el->FindElementValueAsNumberConvertTo("htailarm", "FT");
 169   if (el->FindElement("vtailarea"))
 170     VTailArea = el->FindElementValueAsNumberConvertTo("vtailarea", "FT2");
 171   if (el->FindElement("vtailarm"))
 172     VTailArm = el->FindElementValueAsNumberConvertTo("vtailarm", "FT");
 173
 174   // Find all LOCATION elements that descend from this METRICS branch of the
 175   // config file. This would be CG location, eyepoint, etc.
 176
 177   element = el->FindElement("location");
 178   while (element) {
 179     element_name = element->GetAttributeValue("name");
 180
 181     if (element_name == "AERORP") vXYZrp = element->FindElementTripletConvertTo("IN");
 182     else if (element_name == "EYEPOINT") vXYZep = element->FindElementTripletConvertTo("IN");
 183     else if (element_name == "VRP") vXYZvrp = element->FindElementTripletConvertTo("IN");
 184
 185     element = el->FindNextElement("location");
 186   }
 187
 188   // calculate some derived parameters
 189   if (cbar != 0.0) {
 190     lbarh = HTailArm/cbar;
 191     lbarv = VTailArm/cbar;
 192     if (WingArea != 0.0) {
 193       vbarh = HTailArm*HTailArea / (cbar*WingArea);
 194       vbarv = VTailArm*VTailArea / (cbar*WingArea);
 195     }
 196   }
 197
 198   Debug(2);
 199
 200   return true;
 201 }
 202
 203 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 204
 205 void FGAircraft::bind(void)
 206 {
 207   typedef double (FGAircraft::*PMF)(int) const;
 208   PropertyManager->Tie("metrics/Sw-sqft", this, &FGAircraft::GetWingArea);
 209   PropertyManager->Tie("metrics/bw-ft", this, &FGAircraft::GetWingSpan);
 210   PropertyManager->Tie("metrics/cbarw-ft", this, &FGAircraft::Getcbar);
 211   PropertyManager->Tie("metrics/iw-deg", this, &FGAircraft::GetWingIncidence);
 212   PropertyManager->Tie("metrics/Sh-sqft", this, &FGAircraft::GetHTailArea);
 213   PropertyManager->Tie("metrics/lh-ft", this, &FGAircraft::GetHTailArm);
 214   PropertyManager->Tie("metrics/Sv-sqft", this, &FGAircraft::GetVTailArea);
 215   PropertyManager->Tie("metrics/lv-ft", this, &FGAircraft::GetVTailArm);
 216   PropertyManager->Tie("metrics/lh-norm", this, &FGAircraft::Getlbarh);
 217   PropertyManager->Tie("metrics/lv-norm", this, &FGAircraft::Getlbarv);
 218   PropertyManager->Tie("metrics/vbarh-norm", this, &FGAircraft::Getvbarh);
 219   PropertyManager->Tie("metrics/vbarv-norm", this, &FGAircraft::Getvbarv);
 220   PropertyManager->Tie("forces/hold-down", this, &FGAircraft::GetHoldDown, &FGAircraft::SetHoldDown);
 221   PropertyManager->Tie("moments/l-total-lbsft", this, eL, (PMF)&FGAircraft::GetMoments);
 222   PropertyManager->Tie("moments/m-total-lbsft", this, eM, (PMF)&FGAircraft::GetMoments);
 223   PropertyManager->Tie("moments/n-total-lbsft", this, eN, (PMF)&FGAircraft::GetMoments);
 224   PropertyManager->Tie("forces/fbx-total-lbs", this, eX, (PMF)&FGAircraft::GetForces);
 225   PropertyManager->Tie("forces/fby-total-lbs", this, eY, (PMF)&FGAircraft::GetForces);
 226   PropertyManager->Tie("forces/fbz-total-lbs", this, eZ, (PMF)&FGAircraft::GetForces);
 227   PropertyManager->Tie("metrics/aero-rp-x-in", this, eX, (PMF)&FGAircraft::GetXYZrp);
 228   PropertyManager->Tie("metrics/aero-rp-y-in", this, eY, (PMF)&FGAircraft::GetXYZrp);
 229   PropertyManager->Tie("metrics/aero-rp-z-in", this, eZ, (PMF)&FGAircraft::GetXYZrp);
 230   PropertyManager->Tie("metrics/eyepoint-x-in", this, eX, (PMF)&FGAircraft::GetXYZep);
 231   PropertyManager->Tie("metrics/eyepoint-y-in", this, eY,(PMF)&FGAircraft::GetXYZep);
 232   PropertyManager->Tie("metrics/eyepoint-z-in", this, eZ, (PMF)&FGAircraft::GetXYZep);
 233   PropertyManager->Tie("metrics/visualrefpoint-x-in", this, eX, (PMF)&FGAircraft::GetXYZvrp);
 234   PropertyManager->Tie("metrics/visualrefpoint-y-in", this, eY, (PMF)&FGAircraft::GetXYZvrp);
 235   PropertyManager->Tie("metrics/visualrefpoint-z-in", this, eZ, (PMF)&FGAircraft::GetXYZvrp);
 236 }
 237
 238 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 239
 240 void FGAircraft::unbind(void)
 241 {
 242   PropertyManager->Untie("metrics/Sw-sqft");
 243   PropertyManager->Untie("metrics/bw-ft");
 244   PropertyManager->Untie("metrics/cbarw-ft");
 245   PropertyManager->Untie("metrics/iw-deg");
 246   PropertyManager->Untie("metrics/Sh-sqft");
 247   PropertyManager->Untie("metrics/lh-ft");
 248   PropertyManager->Untie("metrics/Sv-sqft");
 249   PropertyManager->Untie("metrics/lv-ft");
 250   PropertyManager->Untie("metrics/lh-norm");
 251   PropertyManager->Untie("metrics/lv-norm");
 252   PropertyManager->Untie("metrics/vbarh-norm");
 253   PropertyManager->Untie("metrics/vbarv-norm");
 254   PropertyManager->Untie("moments/l-total-lbsft");
 255   PropertyManager->Untie("moments/m-total-lbsft");
 256   PropertyManager->Untie("moments/n-total-lbsft");
 257   PropertyManager->Untie("forces/fbx-total-lbs");
 258   PropertyManager->Untie("forces/fby-total-lbs");
 259   PropertyManager->Untie("forces/fbz-total-lbs");
 260   PropertyManager->Untie("forces/hold-down");
 261   PropertyManager->Untie("metrics/aero-rp-x-in");
 262   PropertyManager->Untie("metrics/aero-rp-y-in");
 263   PropertyManager->Untie("metrics/aero-rp-z-in");
 264   PropertyManager->Untie("metrics/eyepoint-x-in");
 265   PropertyManager->Untie("metrics/eyepoint-y-in");
 266   PropertyManager->Untie("metrics/eyepoint-z-in");
 267   PropertyManager->Untie("metrics/visualrefpoint-x-in");
 268   PropertyManager->Untie("metrics/visualrefpoint-y-in");
 269   PropertyManager->Untie("metrics/visualrefpoint-z-in");
 270 }
 271
 272 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 273 //    The bitmasked value choices are as follows:
 274 //    unset: In this case (the default) JSBSim would only print
 275 //       out the normally expected messages, essentially echoing
 276 //       the config files as they are read. If the environment
 277 //       variable is not set, debug_lvl is set to 1 internally
 278 //    0: This requests JSBSim not to output any messages
 279 //       whatsoever.
 280 //    1: This value explicity requests the normal JSBSim
 281 //       startup messages
 282 //    2: This value asks for a message to be printed out when
 283 //       a class is instantiated
 284 //    4: When this value is set, a message is displayed when a
 285 //       FGModel object executes its Run() method
 286 //    8: When this value is set, various runtime state variables
 287 //       are printed out periodically
 288 //    16: When set various parameters are sanity checked and
 289 //       a message is printed out when they go out of bounds
 290
 291 void FGAircraft::Debug(int from)
 292 {
 293   if (debug_lvl <= 0) return;
 294
 295   if (debug_lvl & 1) { // Standard console startup message output
 296     if (from == 2) { // Loading
 297       cout << endl << "  Aircraft Metrics:" << endl;
 298       cout << "    WingArea: " << WingArea  << endl;
 299       cout << "    WingSpan: " << WingSpan  << endl;
 300       cout << "    Incidence: " << WingIncidence << endl;
 301       cout << "    Chord: " << cbar << endl;
 302       cout << "    H. Tail Area: " << HTailArea << endl;
 303       cout << "    H. Tail Arm: " << HTailArm << endl;
 304       cout << "    V. Tail Area: " << VTailArea << endl;
 305       cout << "    V. Tail Arm: " << VTailArm << endl;
 306       cout << "    Eyepoint (x, y, z): " << vXYZep << endl;
 307       cout << "    Ref Pt (x, y, z): " << vXYZrp << endl;
 308       cout << "    Visual Ref Pt (x, y, z): " << vXYZvrp << endl;
 309     }
 310   }
 311   if (debug_lvl & 2 ) { // Instantiation/Destruction notification
 312     if (from == 0) cout << "Instantiated: FGAircraft" << endl;
 313     if (from == 1) cout << "Destroyed:    FGAircraft" << endl;
 314   }
 315   if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
 316   }
 317   if (debug_lvl & 8 ) { // Runtime state variables
 318   }
 319   if (debug_lvl & 16) { // Sanity checking
 320   }
 321   if (debug_lvl & 64) {
 322     if (from == 0) { // Constructor
 323       cout << IdSrc << endl;
 324       cout << IdHdr << endl;
 325     }
 326   }
 327 }
 328
 329 } // namespace JSBSim