1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
6 Purpose: Encapsulates the inertial frame forces (coriolis and centrifugal)
8 ------------- Copyright (C) 2000 Jon S. Berndt (jsb@hal-pc.org) -------------
10 This program is free software; you can redistribute it and/or modify it under
11 the terms of the GNU Lesser General Public License as published by the Free Software
12 Foundation; either version 2 of the License, or (at your option) any later
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 Lesser General Public License for more
20 You should have received a copy of the GNU Lesser 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.
24 Further information about the GNU Lesser General Public License can also be found on
25 the world wide web at http://www.gnu.org.
27 FUNCTIONAL DESCRIPTION
28 --------------------------------------------------------------------------------
31 --------------------------------------------------------------------------------
34 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
36 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
38 #include "FGInertial.h"
39 #include "FGPropagate.h"
41 #include "FGMassBalance.h"
45 static const char *IdSrc = "$Id$";
46 static const char *IdHdr = ID_INERTIAL;
48 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
50 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
53 FGInertial::FGInertial(FGFDMExec* fgex) : FGModel(fgex)
58 RotationRate = 0.00007292115;
59 GM = 14.07644180E15; // WGS84 value
60 RadiusReference = 20925650.00; // Equatorial radius (WGS84)
61 C2_0 = -4.84165371736E-04; // WGS84 value for the C2,0 coefficient
62 J2 = 1.0826266836E-03; // WGS84 value for J2
63 a = 20925646.3255; // WGS84 semimajor axis length in feet
64 b = 20855486.5951; // WGS84 semiminor axis length in feet
69 RotationRate = 0.0000026617;
70 GM = 1.7314079E14; // Lunar GM
71 RadiusReference = 5702559.05; // Equatorial radius
72 C2_0 = 0; // value for the C2,0 coefficient
73 J2 = 2.033542482111609E-4; // value for J2
74 a = 5702559.05; // semimajor axis length in feet
75 b = 5695439.63; // semiminor axis length in feet
79 gAccelReference = GM/(RadiusReference*RadiusReference);
80 gAccel = GM/(RadiusReference*RadiusReference);
87 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
89 FGInertial::~FGInertial(void)
94 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
96 bool FGInertial::InitModel(void)
98 if (!FGModel::InitModel()) return false;
105 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
107 bool FGInertial::Run(void)
109 // Fast return if we have nothing to do ...
110 if (FGModel::Run()) return true;
111 if (FDMExec->Holding()) return false;
114 double r = Propagate->GetRadius();
115 gAccel = GetGAccel(r);
116 earthPosAngle += State->Getdt()*RotationRate;
121 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
123 double FGInertial::GetGAccel(double r) const
128 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
130 void FGInertial::bind(void)
132 PropertyManager->Tie("position/epa-rad", this, &FGInertial::GetEarthPositionAngle);
135 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
136 // The bitmasked value choices are as follows:
137 // unset: In this case (the default) JSBSim would only print
138 // out the normally expected messages, essentially echoing
139 // the config files as they are read. If the environment
140 // variable is not set, debug_lvl is set to 1 internally
141 // 0: This requests JSBSim not to output any messages
143 // 1: This value explicity requests the normal JSBSim
145 // 2: This value asks for a message to be printed out when
146 // a class is instantiated
147 // 4: When this value is set, a message is displayed when a
148 // FGModel object executes its Run() method
149 // 8: When this value is set, various runtime state variables
150 // are printed out periodically
151 // 16: When set various parameters are sanity checked and
152 // a message is printed out when they go out of bounds
154 void FGInertial::Debug(int from)
156 if (debug_lvl <= 0) return;
158 if (debug_lvl & 1) { // Standard console startup message output
159 if (from == 0) { // Constructor
163 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
164 if (from == 0) cout << "Instantiated: FGInertial" << endl;
165 if (from == 1) cout << "Destroyed: FGInertial" << endl;
167 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
169 if (debug_lvl & 8 ) { // Runtime state variables
171 if (debug_lvl & 16) { // Sanity checking
173 if (debug_lvl & 64) {
174 if (from == 0) { // Constructor
175 cout << IdSrc << endl;
176 cout << IdHdr << endl;