src/FDM/JSBSim/FGGroundReactions.cpp

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Module:       FGGroundReactions.cpp
   4  Author:       Jon S. Berndt
   5  Date started: 09/13/00
   6  Purpose:      Encapsulates the ground reaction forces (gear and collision)
   7
   8  ------------- Copyright (C) 2000  Jon S. Berndt (jsb@hal-pc.org) -------------
   9
  10  This program is free software; you can redistribute it and/or modify it under
  11  the terms of the GNU 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 General Public License for more
  18  details.
  19
  20  You should have received a copy of the GNU 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 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 HISTORY
  31 --------------------------------------------------------------------------------
  32 09/13/00   JSB   Created
  33
  34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  35 INCLUDES
  36 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  37
  38 #include <sstream>
  39 #include <iomanip>
  40
  41 #include "FGGroundReactions.h"
  42 #include "FGPropertyManager.h"
  43
  44 namespace JSBSim {
  45
  46 static const char *IdSrc = "$Id$";
  47 static const char *IdHdr = ID_GROUNDREACTIONS;
  48
  49 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  50 CLASS IMPLEMENTATION
  51 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  52
  53
  54 FGGroundReactions::FGGroundReactions(FGFDMExec* fgex) : FGModel(fgex)
  55 {
  56   Name = "FGGroundReactions";
  57
  58   bind();
  59
  60   Debug(0);
  61 }
  62
  63 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  64
  65 FGGroundReactions::~FGGroundReactions(void)
  66 {
  67   unbind();
  68
  69   Debug(1);
  70 }
  71
  72 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  73
  74 bool FGGroundReactions::Run(void)
  75 {
  76   if (!FGModel::Run()) {
  77     vForces.InitMatrix();
  78     vMoments.InitMatrix();
  79
  80     // Only execute gear force code below 300 feet
  81     if ( Propagate->GetDistanceAGL() < 300.0 ) {
  82       vector <FGLGear>::iterator iGear = lGear.begin();
  83       // Sum forces and moments for all gear, here.
  84       // Some optimizations may be made here - or rather in the gear code itself.
  85       // The gear ::Run() method is called several times - once for each gear.
  86       // Perhaps there is some commonality for things which only need to be
  87       // calculated once.
  88       while (iGear != lGear.end()) {
  89         vForces  += iGear->Force();
  90         vMoments += iGear->Moment();
  91         iGear++;
  92       }
  93
  94     } else {
  95       // Crash Routine
  96     }
  97
  98     return false;
  99   } else {
 100     return true;
 101   }
 102 }
 103
 104 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 105
 106 bool FGGroundReactions::Load(FGConfigFile* AC_cfg)
 107 {
 108   string token;
 109
 110   AC_cfg->GetNextConfigLine();
 111
 112   while ((token = AC_cfg->GetValue()) != string("/UNDERCARRIAGE")) {
 113     lGear.push_back(FGLGear(AC_cfg, FDMExec));
 114   }
 115
 116   return true;
 117 }
 118
 119 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 120
 121 string FGGroundReactions::GetGroundReactionStrings(void)
 122 {
 123   std::ostringstream buf;
 124
 125   for (unsigned int i=0;i<lGear.size();i++) {
 126     string name = lGear[i].GetName();
 127     buf << name << "_WOW, "
 128         << name << "_stroke, "
 129         << name << "_strokeVel, "
 130         << name << "_CompressForce, "
 131         << name << "_WhlSideForce, "
 132         << name << "_WhlVelVecX, "
 133         << name << "_WhlVelVecY, "
 134         << name << "_WhlRollForce, "
 135         << name << "_BodyXForce, "
 136         << name << "_BodyYForce, "
 137         << name << "_WhlSlipDegrees, ";
 138   }
 139
 140   buf << "TotalGearForce_X, "
 141       << "TotalGearForce_Y, "
 142       << "TotalGearForce_Z, "
 143       << "TotalGearMoment_L, "
 144       << "TotalGearMoment_M, "
 145       << "TotalGearMoment_N";
 146
 147   return buf.str();
 148 }
 149
 150 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 151
 152 string FGGroundReactions::GetGroundReactionValues(void)
 153 {
 154   std::ostringstream buf;
 155
 156   for (unsigned int i=0;i<lGear.size();i++) {
 157     FGLGear& gear = lGear[i];
 158     buf << (gear.GetWOW() ? "1, " : "0, ")
 159         << setprecision(5) << gear.GetCompLen() << ", "
 160         << setprecision(6) << gear.GetCompVel() << ", "
 161         << setprecision(10) << gear.GetCompForce() << ", "
 162         << setprecision(6) << gear.GetWheelVel(eX) << ", "
 163         << gear.GetWheelVel(eY) << ", "
 164         << gear.GetWheelSideForce() << ", "
 165         << gear.GetWheelRollForce() << ", "
 166         << gear.GetBodyXForce() << ", "
 167         << gear.GetBodyYForce() << ", "
 168         << gear.GetWheelSlipAngle() << ", ";
 169   }
 170
 171   buf << vForces(eX) << ", "
 172       << vForces(eY) << ", "
 173       << vForces(eZ) << ", "
 174       << vMoments(eX) << ", "
 175       << vMoments(eY) << ", "
 176       << vMoments(eZ);
 177
 178   return buf.str();
 179 }
 180
 181 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 182
 183 void FGGroundReactions::bind(void)
 184 {
 185   typedef double (FGGroundReactions::*PMF)(int) const;
 186   PropertyManager->Tie("gear/num-units", this,
 187                        &FGGroundReactions::GetNumGearUnits);
 188   PropertyManager->Tie("moments/l-gear-lbsft", this,1,
 189                        (PMF)&FGGroundReactions::GetMoments);
 190   PropertyManager->Tie("moments/m-gear-lbsft", this,2,
 191                        (PMF)&FGGroundReactions::GetMoments);
 192   PropertyManager->Tie("moments/n-gear-lbsft", this,3,
 193                        (PMF)&FGGroundReactions::GetMoments);
 194   PropertyManager->Tie("forces/fbx-gear-lbs", this,1,
 195                        (PMF)&FGGroundReactions::GetForces);
 196   PropertyManager->Tie("forces/fby-gear-lbs", this,2,
 197                        (PMF)&FGGroundReactions::GetForces);
 198   PropertyManager->Tie("forces/fbz-gear-lbs", this,3,
 199                        (PMF)&FGGroundReactions::GetForces);
 200 }
 201
 202 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 203
 204 void FGGroundReactions::unbind(void)
 205 {
 206   PropertyManager->Untie("gear/num-units");
 207   PropertyManager->Untie("moments/l-gear-lbsft");
 208   PropertyManager->Untie("moments/m-gear-lbsft");
 209   PropertyManager->Untie("moments/n-gear-lbsft");
 210   PropertyManager->Untie("forces/fbx-gear-lbs");
 211   PropertyManager->Untie("forces/fby-gear-lbs");
 212   PropertyManager->Untie("forces/fbz-gear-lbs");
 213 }
 214
 215 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 216 //    The bitmasked value choices are as follows:
 217 //    unset: In this case (the default) JSBSim would only print
 218 //       out the normally expected messages, essentially echoing
 219 //       the config files as they are read. If the environment
 220 //       variable is not set, debug_lvl is set to 1 internally
 221 //    0: This requests JSBSim not to output any messages
 222 //       whatsoever.
 223 //    1: This value explicity requests the normal JSBSim
 224 //       startup messages
 225 //    2: This value asks for a message to be printed out when
 226 //       a class is instantiated
 227 //    4: When this value is set, a message is displayed when a
 228 //       FGModel object executes its Run() method
 229 //    8: When this value is set, various runtime state variables
 230 //       are printed out periodically
 231 //    16: When set various parameters are sanity checked and
 232 //       a message is printed out when they go out of bounds
 233
 234 void FGGroundReactions::Debug(int from)
 235 {
 236   if (debug_lvl <= 0) return;
 237
 238   if (debug_lvl & 1) { // Standard console startup message output
 239     if (from == 0) { // Constructor
 240
 241     }
 242   }
 243   if (debug_lvl & 2 ) { // Instantiation/Destruction notification
 244     if (from == 0) cout << "Instantiated: FGGroundReactions" << endl;
 245     if (from == 1) cout << "Destroyed:    FGGroundReactions" << endl;
 246   }
 247   if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
 248   }
 249   if (debug_lvl & 8 ) { // Runtime state variables
 250   }
 251   if (debug_lvl & 16) { // Sanity checking
 252   }
 253   if (debug_lvl & 64) {
 254     if (from == 0) { // Constructor
 255       cout << IdSrc << endl;
 256       cout << IdHdr << endl;
 257     }
 258   }
 259 }
 260 }