1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3 Module: FGGroundReactions.cpp
6 Purpose: Encapsulates the ground reaction forces (gear and collision)
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 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
41 #include "FGGroundReactions.h"
42 #include <input_output/FGPropertyManager.h>
46 static const char *IdSrc = "$Id$";
47 static const char *IdHdr = ID_GROUNDREACTIONS;
49 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
51 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
54 FGGroundReactions::FGGroundReactions(FGFDMExec* fgex) : FGModel(fgex)
56 Name = "FGGroundReactions";
63 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
65 FGGroundReactions::~FGGroundReactions(void)
67 for (unsigned int i=0; i<lGear.size();i++) lGear[i].unbind();
74 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
76 bool FGGroundReactions::Run(void)
78 if (FGModel::Run()) return true;
79 if (FDMExec->Holding()) return false;
82 vMoments.InitMatrix();
84 if ( Propagate->GetDistanceAGL() < 300.0 ) { // Only execute gear code below 300 feet
85 vector <FGLGear>::iterator iGear = lGear.begin();
87 // Sum forces and moments for all gear, here.
88 // Some optimizations may be made here - or rather in the gear code itself.
89 // The gear ::Run() method is called several times - once for each gear.
90 // Perhaps there is some commonality for things which only need to be
93 while (iGear != lGear.end()) {
94 vForces += iGear->Force();
95 vMoments += iGear->Moment();
104 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
106 bool FGGroundReactions::GetWOW(void)
109 for (unsigned int i=0; i<lGear.size(); i++) {
110 if (lGear[i].IsBogey() && lGear[i].GetWOW()) {
118 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
120 bool FGGroundReactions::Load(Element* el)
126 Element* contact_element = el->FindElement("contact");
127 while (contact_element) {
128 lGear.push_back(FGLGear(contact_element, FDMExec, num++));
129 FCS->AddGear(); // make the FCS aware of the landing gear
130 contact_element = el->FindNextElement("contact");
133 for (unsigned int i=0; i<lGear.size();i++) lGear[i].bind();
138 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
140 string FGGroundReactions::GetGroundReactionStrings(string delimeter)
142 std::ostringstream buf;
144 for (unsigned int i=0;i<lGear.size();i++) {
145 if (lGear[i].IsBogey()) {
146 string name = lGear[i].GetName();
147 buf << name << " WOW" << delimeter
148 << name << " stroke (ft)" << delimeter
149 << name << " stroke velocity (ft/sec)" << delimeter
150 << name << " compress force (lbs)" << delimeter
151 << name << " wheel side force (lbs)" << delimeter
152 << name << " wheel roll force (lbs)" << delimeter
153 << name << " body X force (lbs)" << delimeter
154 << name << " body Y force (lbs)" << delimeter
155 << name << " wheel velocity vec X (ft/sec)" << delimeter
156 << name << " wheel velocity vec Y (ft/sec)" << delimeter
157 << name << " wheel rolling velocity (ft/sec)" << delimeter
158 << name << " wheel side velocity (ft/sec)" << delimeter
159 << name << " wheel slip (deg)" << delimeter;
163 buf << " Total Gear Force_X (lbs)" << delimeter
164 << " Total Gear Force_Y (lbs)" << delimeter
165 << " Total Gear Force_Z (lbs)" << delimeter
166 << " Total Gear Moment_L (ft-lbs)" << delimeter
167 << " Total Gear Moment_M (ft-lbs)" << delimeter
168 << " Total Gear Moment_N (ft-lbs)";
173 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
175 string FGGroundReactions::GetGroundReactionValues(string delimeter)
177 std::ostringstream buf;
179 for (unsigned int i=0;i<lGear.size();i++) {
180 if (lGear[i].IsBogey()) {
181 FGLGear& gear = lGear[i];
182 buf << (gear.GetWOW() ? "1, " : "0, ")
183 << setprecision(5) << gear.GetCompLen() << delimeter
184 << setprecision(6) << gear.GetCompVel() << delimeter
185 << setprecision(10) << gear.GetCompForce() << delimeter
186 << gear.GetWheelSideForce() << delimeter
187 << gear.GetWheelRollForce() << delimeter
188 << gear.GetBodyXForce() << delimeter
189 << gear.GetBodyYForce() << delimeter
190 << setprecision(6) << gear.GetWheelVel(eX) << delimeter
191 << gear.GetWheelVel(eY) << delimeter
192 << gear.GetWheelRollVel() << delimeter
193 << gear.GetWheelSideVel() << delimeter
194 << gear.GetWheelSlipAngle() << delimeter;
198 buf << vForces(eX) << delimeter
199 << vForces(eY) << delimeter
200 << vForces(eZ) << delimeter
201 << vMoments(eX) << delimeter
202 << vMoments(eY) << delimeter
208 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
210 void FGGroundReactions::bind(void)
212 typedef double (FGGroundReactions::*PMF)(int) const;
213 PropertyManager->Tie("gear/num-units", this, &FGGroundReactions::GetNumGearUnits);
214 PropertyManager->Tie("moments/l-gear-lbsft", this, eL, (PMF)&FGGroundReactions::GetMoments);
215 PropertyManager->Tie("moments/m-gear-lbsft", this, eM, (PMF)&FGGroundReactions::GetMoments);
216 PropertyManager->Tie("moments/n-gear-lbsft", this, eN, (PMF)&FGGroundReactions::GetMoments);
217 PropertyManager->Tie("forces/fbx-gear-lbs", this, eX, (PMF)&FGGroundReactions::GetForces);
218 PropertyManager->Tie("forces/fby-gear-lbs", this, eY, (PMF)&FGGroundReactions::GetForces);
219 PropertyManager->Tie("forces/fbz-gear-lbs", this, eZ, (PMF)&FGGroundReactions::GetForces);
222 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
224 void FGGroundReactions::unbind(void)
226 PropertyManager->Untie("gear/num-units");
227 PropertyManager->Untie("moments/l-gear-lbsft");
228 PropertyManager->Untie("moments/m-gear-lbsft");
229 PropertyManager->Untie("moments/n-gear-lbsft");
230 PropertyManager->Untie("forces/fbx-gear-lbs");
231 PropertyManager->Untie("forces/fby-gear-lbs");
232 PropertyManager->Untie("forces/fbz-gear-lbs");
235 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
236 // The bitmasked value choices are as follows:
237 // unset: In this case (the default) JSBSim would only print
238 // out the normally expected messages, essentially echoing
239 // the config files as they are read. If the environment
240 // variable is not set, debug_lvl is set to 1 internally
241 // 0: This requests JSBSim not to output any messages
243 // 1: This value explicity requests the normal JSBSim
245 // 2: This value asks for a message to be printed out when
246 // a class is instantiated
247 // 4: When this value is set, a message is displayed when a
248 // FGModel object executes its Run() method
249 // 8: When this value is set, various runtime state variables
250 // are printed out periodically
251 // 16: When set various parameters are sanity checked and
252 // a message is printed out when they go out of bounds
254 void FGGroundReactions::Debug(int from)
256 if (debug_lvl <= 0) return;
258 if (debug_lvl & 1) { // Standard console startup message output
259 if (from == 2) { // Loading
260 cout << endl << " Ground Reactions: " << endl;
263 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
264 if (from == 0) cout << "Instantiated: FGGroundReactions" << endl;
265 if (from == 1) cout << "Destroyed: FGGroundReactions" << endl;
267 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
269 if (debug_lvl & 8 ) { // Runtime state variables
271 if (debug_lvl & 16) { // Sanity checking
273 if (debug_lvl & 64) {
274 if (from == 0) { // Constructor
275 cout << IdSrc << endl;
276 cout << IdHdr << endl;