src/FDM/JSBSim/models/FGMassBalance.h

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Header:       FGMassBalance.h
   4  Author:       Jon S. Berndt
   5  Date started: 09/12/2000
   6
   7  ------------- Copyright (C) 2000  Jon S. Berndt (jsb@hal-pc.org) --------------
   8
   9  This program is free software; you can redistribute it and/or modify it under
  10  the terms of the GNU Lesser General Public License as published by the Free Software
  11  Foundation; either version 2 of the License, or (at your option) any later
  12  version.
  13
  14  This program is distributed in the hope that it will be useful, but WITHOUT
  15  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  16  FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
  17  details.
  18
  19  You should have received a copy of the GNU Lesser General Public License along with
  20  this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  21  Place - Suite 330, Boston, MA  02111-1307, USA.
  22
  23  Further information about the GNU Lesser General Public License can also be found on
  24  the world wide web at http://www.gnu.org.
  25
  26 HISTORY
  27 --------------------------------------------------------------------------------
  28 09/12/2000  JSB  Created
  29
  30 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  31 SENTRY
  32 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  33
  34 #ifndef FGMASSBALANCE_H
  35 #define FGMASSBALANCE_H
  36
  37 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  38 INCLUDES
  39 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  40
  41 #include "FGModel.h"
  42 #include <math/FGColumnVector3.h>
  43 #include <math/FGMatrix33.h>
  44 #include <input_output/FGXMLElement.h>
  45 #include <vector>
  46
  47 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  48 DEFINITIONS
  49 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  50
  51 #define ID_MASSBALANCE "$Id$"
  52
  53 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  54 FORWARD DECLARATIONSS
  55 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  56
  57 namespace JSBSim {
  58
  59 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  60 CLASS DOCUMENTATION
  61 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  62
  63 /** Models weight, balance and moment of inertia information.  Maintains a vector
  64     of point masses. Sums the contribution of all, and provides this to FGPropagate.
  65     Loads the \<mass_balance> section of the aircraft configuration file.
  66
  67     <h3>Configuration File Format:</h3>
  68 @code
  69     <mass_balance>
  70         <ixx unit="{SLUG*FT2 | KG*M2}"> {number} </ixx>
  71         <iyy unit="{SLUG*FT2 | KG*M2}"> {number} </iyy>
  72         <izz unit="{SLUG*FT2 | KG*M2}"> {number} </izz>
  73         <ixy unit="{SLUG*FT2 | KG*M2}"> {number} </ixy>
  74         <ixz unit="{SLUG*FT2 | KG*M2}"> {number} </ixz>
  75         <iyz unit="{SLUG*FT2 | KG*M2}"> {number} </iyz>
  76         <emptywt unit="{LBS | KG"> {number} </emptywt>
  77         <location name="CG" unit="{IN | M}">
  78             <x> {number} </x>
  79             <y> {number} </y>
  80             <z> {number} </z>
  81         </location>
  82         <pointmass name="{string}">
  83             <weight unit="{LBS | KG}"> {number} </weight>
  84             <location name="POINTMASS" unit="{IN | M}">
  85                 <x> {number} </x>
  86                 <y> {number} </y>
  87                 <z> {number} </z>
  88             </location>
  89         </pointmass>
  90         ... other point masses ...
  91     </mass_balance>
  92 @endcode
  93   */
  94
  95 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  96 CLASS DECLARATION
  97 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  98
  99 class FGMassBalance : public FGModel
 100 {
 101
 102 public:
 103   FGMassBalance(FGFDMExec*);
 104   ~FGMassBalance();
 105
 106   bool Load(Element* el);
 107   bool InitModel(void);
 108   bool Run(void);
 109
 110   double GetMass(void) const {return Mass;}
 111   double GetWeight(void) const {return Weight;}
 112   FGColumnVector3& GetXYZcg(void) {return vXYZcg;}
 113   double GetXYZcg(int axis) const  {return vXYZcg(axis);}
 114   FGColumnVector3& GetDeltaXYZcg(void) {return vDeltaXYZcg;}
 115   double GetDeltaXYZcg(int axis) const  {return vDeltaXYZcg(axis);}
 116
 117   /** Computes the inertia contribution of a pointmass.
 118       Computes and returns the inertia matrix of a pointmass of mass
 119       slugs at the given vector r in the structural frame. The units
 120       should be for the mass in slug and the vector in the structural
 121       frame as usual in inches.
 122       @param slugs the mass of this single pointmass given in slugs
 123       @param r the location of this single pointmass in the structural frame
 124    */
 125   FGMatrix33 GetPointmassInertia(double slugs, const FGColumnVector3& r) const
 126   {
 127     FGColumnVector3 v = StructuralToBody( r );
 128     FGColumnVector3 sv = slugs*v;
 129     double xx = sv(1)*v(1);
 130     double yy = sv(2)*v(2);
 131     double zz = sv(3)*v(3);
 132     double xy = -sv(1)*v(2);
 133     double xz = -sv(1)*v(3);
 134     double yz = -sv(2)*v(3);
 135     return FGMatrix33( yy+zz, xy, xz,
 136                        xy, xx+zz, yz,
 137                        xz, yz, xx+yy );
 138   }
 139
 140   /** Conversion from the structural frame to the body frame.
 141       Converts the location given in the structural frame
 142       coordinate system to the body frame. The units of the structural
 143       frame are assumed to be in inches. The unit of the result is in
 144       ft.
 145       @param r vector coordinate in the structural reference frame (X positive
 146                aft, measurements in inches).
 147       @return vector coordinate in the body frame, in feet.
 148    */
 149   FGColumnVector3 StructuralToBody(const FGColumnVector3& r) const;
 150
 151   inline void SetEmptyWeight(double EW) { EmptyWeight = EW;}
 152   inline void SetBaseCG(const FGColumnVector3& CG) {vbaseXYZcg = vXYZcg = CG;}
 153
 154   void AddPointMass(Element* el);
 155   double GetTotalPointMassWeight(void);
 156
 157   FGColumnVector3& GetPointMassMoment(void);
 158   FGMatrix33& GetJ(void) {return mJ;}
 159   FGMatrix33& GetJinv(void) {return mJinv;}
 160   void SetAircraftBaseInertias(FGMatrix33 BaseJ) {baseJ = BaseJ;}
 161
 162 private:
 163   double Weight;
 164   double EmptyWeight;
 165   double Mass;
 166   FGMatrix33 mJ;
 167   FGMatrix33 mJinv;
 168   FGMatrix33 pmJ;
 169   FGMatrix33 baseJ;
 170   FGColumnVector3 vXYZcg;
 171   FGColumnVector3 vLastXYZcg;
 172   FGColumnVector3 vDeltaXYZcg;
 173   FGColumnVector3 vDeltaXYZcgBody;
 174   FGColumnVector3 vXYZtank;
 175   FGColumnVector3 vbaseXYZcg;
 176   FGColumnVector3 vPMxyz;
 177   FGColumnVector3 PointMassCG;
 178   FGMatrix33& CalculatePMInertias(void);
 179
 180   struct PointMass {
 181     PointMass(double w, FGColumnVector3& vXYZ) {
 182       Weight = w;
 183       Location = vXYZ;
 184     }
 185     FGColumnVector3 Location;
 186     double Weight;
 187     double GetPointMassLocation(int axis) const {return Location(axis);}
 188     void SetPointMassLocation(int axis, double value) {Location(axis) = value;}
 189     void SetPointMassWeight(double wt) {Weight = wt;}
 190     double GetPointMassWeight(void) const {return Weight;}
 191
 192     void bind(FGPropertyManager* PropertyManager, int num) {
 193       string tmp = CreateIndexedPropertyName("inertia/pointmass-weight-lbs", num);
 194       PropertyManager->Tie( tmp.c_str(), this, &PointMass::GetPointMassWeight,
 195                                        &PointMass::SetPointMassWeight);
 196
 197       tmp = CreateIndexedPropertyName("inertia/pointmass-location-X-inches", num);
 198       PropertyManager->Tie( tmp.c_str(), this, eX, &PointMass::GetPointMassLocation,
 199                                            &PointMass::SetPointMassLocation);
 200       tmp = CreateIndexedPropertyName("inertia/pointmass-location-Y-inches", num);
 201       PropertyManager->Tie( tmp.c_str(), this, eY, &PointMass::GetPointMassLocation,
 202                                            &PointMass::SetPointMassLocation);
 203       tmp = CreateIndexedPropertyName("inertia/pointmass-location-Z-inches", num);
 204       PropertyManager->Tie( tmp.c_str(), this, eZ, &PointMass::GetPointMassLocation,
 205                                            &PointMass::SetPointMassLocation);
 206     }
 207   };
 208
 209   vector <struct PointMass*> PointMasses;
 210
 211   void bind(void);
 212   void Debug(int from);
 213 };
 214 }
 215 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 216 #endif