src/FDM/JSBSim/FGAerodynamics.cpp

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Module:       FGAerodynamics.cpp
   4  Author:       Jon S. Berndt
   5  Date started: 09/13/00
   6  Purpose:      Encapsulates the aerodynamic 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 04/22/01   JSB   Moved code into here from FGAircraft
  34
  35 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  36 INCLUDES
  37 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  38
  39 #include "FGAerodynamics.h"
  40 #include "FGFactorGroup.h"
  41 #include "FGCoefficient.h"
  42
  43 static const char *IdSrc = "$Id$";
  44 static const char *IdHdr = ID_AERODYNAMICS;
  45
  46 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  47 CLASS IMPLEMENTATION
  48 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  49
  50
  51 FGAerodynamics::FGAerodynamics(FGFDMExec* FDMExec) : FGModel(FDMExec)
  52 {
  53   Name = "FGAerodynamics";
  54
  55   AxisIdx["DRAG"]  = 0;
  56   AxisIdx["SIDE"]  = 1;
  57   AxisIdx["LIFT"]  = 2;
  58   AxisIdx["ROLL"]  = 3;
  59   AxisIdx["PITCH"] = 4;
  60   AxisIdx["YAW"]   = 5;
  61
  62   Coeff = new CoeffArray[6];
  63
  64   if (debug_lvl & 2) cout << "Instantiated: FGAerodynamics" << endl;
  65 }
  66
  67 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  68
  69 FGAerodynamics::~FGAerodynamics()
  70 {
  71   unsigned int i,j;
  72   for (i=0; i<6; i++) {
  73     for (j=0; j<Coeff[i].size(); j++) {
  74       delete Coeff[i][j];
  75     }
  76   }
  77   delete[] Coeff;
  78
  79   if (debug_lvl & 2) cout << "Destroyed:    FGAerodynamics" << endl;
  80 }
  81
  82 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  83
  84 bool FGAerodynamics::Run(void)
  85 {
  86   unsigned int axis_ctr,ctr;
  87
  88   if (!FGModel::Run()) {
  89
  90     vLastFs = vFs;
  91     vFs.InitMatrix();
  92
  93     for (axis_ctr = 0; axis_ctr < 3; axis_ctr++) {
  94       for (ctr=0; ctr < Coeff[axis_ctr].size(); ctr++) {
  95         vFs(axis_ctr+1) += Coeff[axis_ctr][ctr]->TotalValue();
  96       }
  97     }
  98     //correct signs of drag and lift to wind axes convention
  99     //positive forward, right, down
 100     vFs(1)*=-1; vFs(3)*=-1;
 101     //cout << "Aircraft::vFs: " << vFs << endl;
 102     vForces = State->GetTs2b()*vFs;
 103
 104     vDXYZcg(eX) = -(Aircraft->GetXYZrp(eX)
 105                       - MassBalance->GetXYZcg(eX))*inchtoft;
 106     vDXYZcg(eY) =  (Aircraft->GetXYZrp(eY)
 107                       - MassBalance->GetXYZcg(eY))*inchtoft;
 108     vDXYZcg(eZ) = -(Aircraft->GetXYZrp(eZ)
 109                       - MassBalance->GetXYZcg(eZ))*inchtoft;
 110
 111     vMoments = vDXYZcg*vForces; // M = r X F
 112
 113     for (axis_ctr = 0; axis_ctr < 3; axis_ctr++) {
 114       for (ctr = 0; ctr < Coeff[axis_ctr+3].size(); ctr++) {
 115         vMoments(axis_ctr+1) += Coeff[axis_ctr+3][ctr]->TotalValue();
 116       }
 117     }
 118     return false;
 119   } else {
 120     return true;
 121   }
 122 }
 123
 124 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 125
 126 bool FGAerodynamics::Load(FGConfigFile* AC_cfg)
 127 {
 128   string token, axis;
 129
 130   AC_cfg->GetNextConfigLine();
 131
 132   while ((token = AC_cfg->GetValue()) != string("/AERODYNAMICS")) {
 133     if (token == "AXIS") {
 134       CoeffArray ca;
 135       axis = AC_cfg->GetValue("NAME");
 136       AC_cfg->GetNextConfigLine();
 137       while ((token = AC_cfg->GetValue()) != string("/AXIS")) {
 138         if( token == "COEFFICIENT" ) {
 139           ca.push_back( new FGCoefficient(FDMExec) );
 140           ca.back()->Load(AC_cfg);
 141         } else if ( token == "GROUP" ) {
 142           ca.push_back( new FGFactorGroup(FDMExec) );
 143           ca.back()->Load(AC_cfg);
 144         }
 145       }
 146       Coeff[AxisIdx[axis]] = ca;
 147       AC_cfg->GetNextConfigLine();
 148     }
 149   }
 150
 151   return true;
 152 }
 153
 154 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 155
 156 string FGAerodynamics::GetCoefficientStrings(void)
 157 {
 158   string CoeffStrings = "";
 159   bool firstime = true;
 160   unsigned int axis, sd;
 161
 162   for (axis = 0; axis < 6; axis++) {
 163     for (sd = 0; sd < Coeff[axis].size(); sd++) {
 164       if (firstime) {
 165         firstime = false;
 166       } else {
 167         CoeffStrings += ", ";
 168       }
 169       CoeffStrings += Coeff[axis][sd]->GetCoefficientStrings();
 170     }
 171   }
 172   return CoeffStrings;
 173 }
 174
 175 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 176
 177 string FGAerodynamics::GetCoefficientValues(void)
 178 {
 179   string SDValues = "";
 180   bool firstime = true;
 181
 182   for (unsigned int axis = 0; axis < 6; axis++) {
 183     for (unsigned int sd = 0; sd < Coeff[axis].size(); sd++) {
 184       if (firstime) {
 185         firstime = false;
 186       } else {
 187         SDValues += ", ";
 188       }
 189       SDValues += Coeff[axis][sd]->GetCoefficientValues();
 190     }
 191   }
 192
 193   return SDValues;
 194 }
 195
 196 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 197
 198 double FGAerodynamics::GetLoD(void)
 199 {
 200   if (vFs(1) != 0.00) return vFs(3)/vFs(1);
 201   else                return 0.00;
 202 }
 203
 204 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 205
 206 void FGAerodynamics::Debug(void)
 207 {
 208     //TODO: Add your source code here
 209 }
 210