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 "FGGroundReactions.h"
  39 #include "FGPropertyManager.h"
  40
  41 static const char *IdSrc = "$Id$";
  42 static const char *IdHdr = ID_GROUNDREACTIONS;
  43
  44 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  45 CLASS IMPLEMENTATION
  46 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  47
  48
  49 FGGroundReactions::FGGroundReactions(FGFDMExec* fgex) : FGModel(fgex)
  50 {
  51   Name = "FGGroundReactions";
  52
  53   bind();
  54
  55   Debug(0);
  56 }
  57
  58 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  59
  60 FGGroundReactions::~FGGroundReactions(void)
  61 {
  62   unbind();
  63
  64   Debug(1);
  65 }
  66
  67 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  68
  69 bool FGGroundReactions::Run(void)
  70 {
  71   if (!FGModel::Run()) {
  72     vForces.InitMatrix();
  73     vMoments.InitMatrix();
  74
  75     // Only execute gear force code below 300 feet
  76     if ( Position->GetDistanceAGL() < 300.0 ) {
  77       vector <FGLGear>::iterator iGear = lGear.begin();
  78       // Sum forces and moments for all gear, here.
  79       // Some optimizations may be made here - or rather in the gear code itself.
  80       // The gear ::Run() method is called several times - once for each gear.
  81       // Perhaps there is some commonality for things which only need to be
  82       // calculated once.
  83       while (iGear != lGear.end()) {
  84         vForces  += iGear->Force();
  85         vMoments += iGear->Moment();
  86         iGear++;
  87       }
  88
  89     } else {
  90       // Crash Routine
  91     }
  92
  93     return false;
  94   } else {
  95     return true;
  96   }
  97 }
  98
  99 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 100
 101 bool FGGroundReactions::Load(FGConfigFile* AC_cfg)
 102 {
 103   string token;
 104
 105   AC_cfg->GetNextConfigLine();
 106
 107   while ((token = AC_cfg->GetValue()) != string("/UNDERCARRIAGE")) {
 108     lGear.push_back(FGLGear(AC_cfg, FDMExec));
 109   }
 110
 111   return true;
 112 }
 113
 114 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 115
 116 string FGGroundReactions::GetGroundReactionStrings(void)
 117 {
 118   string GroundReactionStrings = "";
 119   bool firstime = true;
 120
 121   for (unsigned int i=0;i<lGear.size();i++) {
 122     if (!firstime) GroundReactionStrings += ", ";
 123     GroundReactionStrings += (lGear[i].GetName() + "_WOW, ");
 124     GroundReactionStrings += (lGear[i].GetName() + "_stroke, ");
 125     GroundReactionStrings += (lGear[i].GetName() + "_strokeVel, ");
 126     GroundReactionStrings += (lGear[i].GetName() + "_CompressForce, ");
 127     GroundReactionStrings += (lGear[i].GetName() + "_WhlSideForce, ");
 128     GroundReactionStrings += (lGear[i].GetName() + "_WhlRollForce, ");
 129     GroundReactionStrings += (lGear[i].GetName() + "_BodyXForce, ");
 130     GroundReactionStrings += (lGear[i].GetName() + "_BodyYForce, ");
 131     GroundReactionStrings += (lGear[i].GetName() + "_WhlSlipDegrees");
 132
 133     firstime = false;
 134   }
 135
 136   return GroundReactionStrings;
 137 }
 138
 139 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 140
 141 string FGGroundReactions::GetGroundReactionValues(void)
 142 {
 143   char buff[20];
 144   string GroundReactionValues = "";
 145
 146   bool firstime = true;
 147
 148   for (unsigned int i=0;i<lGear.size();i++) {
 149     if (!firstime) GroundReactionValues += ", ";
 150     GroundReactionValues += string( lGear[i].GetWOW()?"1":"0" ) + ", ";
 151     GroundReactionValues += (string(gcvt(lGear[i].GetCompLen(),    5, buff)) + ", ");
 152     GroundReactionValues += (string(gcvt(lGear[i].GetCompVel(),    6, buff)) + ", ");
 153     GroundReactionValues += (string(gcvt(lGear[i].GetCompForce(), 10, buff)) + ", ");
 154     GroundReactionValues += (string(gcvt(lGear[i].GetWheelSideForce(), 6, buff)) + ", ");
 155     GroundReactionValues += (string(gcvt(lGear[i].GetWheelRollForce(), 6, buff)) + ", ");
 156     GroundReactionValues += (string(gcvt(lGear[i].GetBodyXForce(), 6, buff)) + ", ");
 157     GroundReactionValues += (string(gcvt(lGear[i].GetBodyYForce(), 6, buff)) + ", ");
 158     GroundReactionValues += (string(gcvt(lGear[i].GetWheelSlipAngle(), 6, buff)));
 159
 160     firstime = false;
 161   }
 162
 163   return GroundReactionValues;
 164 }
 165
 166 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 167 //    The bitmasked value choices are as follows:
 168 //    unset: In this case (the default) JSBSim would only print
 169 //       out the normally expected messages, essentially echoing
 170 //       the config files as they are read. If the environment
 171 //       variable is not set, debug_lvl is set to 1 internally
 172 //    0: This requests JSBSim not to output any messages
 173 //       whatsoever.
 174 //    1: This value explicity requests the normal JSBSim
 175 //       startup messages
 176 //    2: This value asks for a message to be printed out when
 177 //       a class is instantiated
 178 //    4: When this value is set, a message is displayed when a
 179 //       FGModel object executes its Run() method
 180 //    8: When this value is set, various runtime state variables
 181 //       are printed out periodically
 182 //    16: When set various parameters are sanity checked and
 183 //       a message is printed out when they go out of bounds
 184
 185 void FGGroundReactions::Debug(int from)
 186 {
 187   if (debug_lvl <= 0) return;
 188
 189   if (debug_lvl & 1) { // Standard console startup message output
 190     if (from == 0) { // Constructor
 191
 192     }
 193   }
 194   if (debug_lvl & 2 ) { // Instantiation/Destruction notification
 195     if (from == 0) cout << "Instantiated: FGGroundReactions" << endl;
 196     if (from == 1) cout << "Destroyed:    FGGroundReactions" << endl;
 197   }
 198   if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
 199   }
 200   if (debug_lvl & 8 ) { // Runtime state variables
 201   }
 202   if (debug_lvl & 16) { // Sanity checking
 203   }
 204   if (debug_lvl & 64) {
 205     if (from == 0) { // Constructor
 206       cout << IdSrc << endl;
 207       cout << IdHdr << endl;
 208     }
 209   }
 210 }
 211
 212 void FGGroundReactions::bind(void){
 213
 214   PropertyManager->Tie("gear/num-units", this,
 215                        &FGGroundReactions::GetNumGearUnits);
 216   PropertyManager->Tie("moments/l-gear-lbsft", this,1,
 217                        &FGGroundReactions::GetMoments);
 218   PropertyManager->Tie("moments/m-gear-lbsft", this,2,
 219                        &FGGroundReactions::GetMoments);
 220   PropertyManager->Tie("moments/n-gear-lbsft", this,3,
 221                        &FGGroundReactions::GetMoments);
 222   PropertyManager->Tie("forces/fbx-gear-lbs", this,1,
 223                        &FGGroundReactions::GetForces);
 224   PropertyManager->Tie("forces/fby-gear-lbs", this,2,
 225                        &FGGroundReactions::GetForces);
 226   PropertyManager->Tie("forces/fbz-gear-lbs", this,3,
 227                        &FGGroundReactions::GetForces);
 228 }
 229
 230 void FGGroundReactions::unbind(void){
 231   PropertyManager->Untie("gear/num-units");
 232   PropertyManager->Untie("moments/l-gear-lbsft");
 233   PropertyManager->Untie("moments/m-gear-lbsft");
 234   PropertyManager->Untie("moments/n-gear-lbsft");
 235   PropertyManager->Untie("forces/fbx-gear-lbs");
 236   PropertyManager->Untie("forces/fby-gear-lbs");
 237   PropertyManager->Untie("forces/fbz-gear-lbs");
 238 }