1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3 Module: FGAerodynamics.cpp
6 Purpose: Encapsulates the aerodynamic 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 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 General Public License for more
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.
24 Further information about the GNU General Public License can also be found on
25 the world wide web at http://www.gnu.org.
27 FUNCTIONAL DESCRIPTION
28 --------------------------------------------------------------------------------
31 --------------------------------------------------------------------------------
33 04/22/01 JSB Moved code into here from FGAircraft
35 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
37 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
39 #include "FGAerodynamics.h"
40 #include "FGFactorGroup.h"
41 #include "FGCoefficient.h"
42 #include "FGPropertyManager.h"
46 static const char *IdSrc = "$Id$";
47 static const char *IdHdr = ID_AERODYNAMICS;
49 const unsigned NAxes=6;
50 const char* AxisNames[] = { "drag", "side-force", "lift", "rolling-moment",
51 "pitching-moment","yawing-moment" };
53 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
55 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
58 FGAerodynamics::FGAerodynamics(FGFDMExec* FDMExec) : FGModel(FDMExec)
60 Name = "FGAerodynamics";
69 Coeff = new CoeffArray[6];
71 impending_stall = stall_hyst = 0.0;
72 alphaclmin = alphaclmax = 0.0;
73 alphahystmin = alphahystmax = 0.0;
76 bi2vel = ci2vel = 0.0;
82 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
84 FGAerodynamics::~FGAerodynamics()
91 for (j=0; j<Coeff[i].size(); j++) {
100 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
102 bool FGAerodynamics::Run(void)
104 unsigned int axis_ctr,ctr;
105 double alpha, twovel;
107 if (!FGModel::Run()) {
109 twovel = 2*Translation->GetVt();
111 bi2vel = Aircraft->GetWingSpan() / twovel;
112 ci2vel = Aircraft->Getcbar() / twovel;
115 alphaw = Translation->Getalpha() + Aircraft->GetWingIncidence();
117 alpha = Translation->Getalpha();
119 if (alphaclmax != 0) {
120 if (alpha > 0.85*alphaclmax) {
121 impending_stall = 10*(alpha/alphaclmax - 0.85);
127 if (alphahystmax != 0.0 && alphahystmin != 0.0) {
128 if (alpha > alphahystmax) {
130 } else if (alpha < alphahystmin) {
138 for (axis_ctr = 0; axis_ctr < 3; axis_ctr++) {
139 for (ctr=0; ctr < Coeff[axis_ctr].size(); ctr++) {
140 vFs(axis_ctr+1) += Coeff[axis_ctr][ctr]->TotalValue();
144 //correct signs of drag and lift to wind axes convention
145 //positive forward, right, down
146 if ( Translation->Getqbar() > 0) {
147 clsq = vFs(eLift) / (Aircraft->GetWingArea()*Translation->Getqbar());
150 if ( vFs(eDrag) > 0) {
151 lod = vFs(eLift) / vFs(eDrag);
154 //correct signs of drag and lift to wind axes convention
155 //positive forward, right, down
156 vFs(eDrag)*=-1; vFs(eLift)*=-1;
158 vForces = State->GetTs2b()*vFs;
160 vDXYZcg = MassBalance->StructuralToBody(Aircraft->GetXYZrp());
162 vMoments = vDXYZcg*vForces; // M = r X F
164 for (axis_ctr = 0; axis_ctr < 3; axis_ctr++) {
165 for (ctr = 0; ctr < Coeff[axis_ctr+3].size(); ctr++) {
166 vMoments(axis_ctr+1) += Coeff[axis_ctr+3][ctr]->TotalValue();
176 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
178 bool FGAerodynamics::Load(FGConfigFile* AC_cfg)
180 string parameter, axis, scratch;
182 AC_cfg->GetNextConfigLine();
184 while ((parameter = AC_cfg->GetValue()) != string("/AERODYNAMICS")) {
185 if (parameter == "AXIS") {
187 axis = AC_cfg->GetValue("NAME");
188 AC_cfg->GetNextConfigLine();
189 while ((parameter = AC_cfg->GetValue()) != string("/AXIS")) {
190 if ( parameter == "COEFFICIENT" ) {
191 ca.push_back( new FGCoefficient(FDMExec) );
192 ca.back()->Load(AC_cfg);
193 } else if ( parameter == "GROUP" ) {
194 ca.push_back( new FGFactorGroup(FDMExec) );
195 ca.back()->Load(AC_cfg);
198 Coeff[AxisIdx[axis]] = ca;
199 AC_cfg->GetNextConfigLine();
200 } else if (parameter == "AC_ALPHALIMITS") {
201 *AC_cfg >> scratch >> alphaclmin >> alphaclmax;
202 if (debug_lvl > 0) cout << " Maximum Alpha: " << alphaclmax
203 << " Minimum Alpha: " << alphaclmin
205 } else if (parameter == "AC_HYSTLIMITS") {
206 *AC_cfg >> scratch >> alphahystmin >> alphahystmax;
207 if (debug_lvl > 0) cout << " Hysteresis Start: " << alphahystmax
208 << " Hysteresis End: " << alphahystmin
218 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
220 string FGAerodynamics::GetCoefficientStrings(void)
222 string CoeffStrings = "";
223 bool firstime = true;
224 unsigned int axis, sd;
226 for (axis = 0; axis < 6; axis++) {
227 for (sd = 0; sd < Coeff[axis].size(); sd++) {
231 CoeffStrings += ", ";
233 CoeffStrings += Coeff[axis][sd]->GetCoefficientName();
239 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
241 string FGAerodynamics::GetCoefficientValues(void)
243 string SDValues = "";
244 bool firstime = true;
246 for (unsigned int axis = 0; axis < 6; axis++) {
247 for (unsigned int sd = 0; sd < Coeff[axis].size(); sd++) {
253 SDValues += Coeff[axis][sd]->GetSDstring();
260 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
262 void FGAerodynamics::bind(void)
264 typedef double (FGAerodynamics::*PMF)(int) const;
266 PropertyManager->Tie("forces/fbx-aero-lbs", this,1,
267 (PMF)&FGAerodynamics::GetForces);
268 PropertyManager->Tie("forces/fby-aero-lbs", this,2,
269 (PMF)&FGAerodynamics::GetForces);
270 PropertyManager->Tie("forces/fbz-aero-lbs", this,3,
271 (PMF)&FGAerodynamics::GetForces);
272 PropertyManager->Tie("moments/l-aero-lbsft", this,1,
273 (PMF)&FGAerodynamics::GetMoments);
274 PropertyManager->Tie("moments/m-aero-lbsft", this,2,
275 (PMF)&FGAerodynamics::GetMoments);
276 PropertyManager->Tie("moments/n-aero-lbsft", this,3,
277 (PMF)&FGAerodynamics::GetMoments);
278 PropertyManager->Tie("forces/fwx-aero-lbs", this,1,
279 (PMF)&FGAerodynamics::GetvFs);
280 PropertyManager->Tie("forces/fwy-aero-lbs", this,2,
281 (PMF)&FGAerodynamics::GetvFs);
282 PropertyManager->Tie("forces/fwz-aero-lbs", this,3,
283 (PMF)&FGAerodynamics::GetvFs);
284 PropertyManager->Tie("forces/lod-norm", this,
285 &FGAerodynamics::GetLoD);
286 PropertyManager->Tie("aero/cl-squared-norm", this,
287 &FGAerodynamics::GetClSquared);
288 PropertyManager->Tie("aero/alpha-max-deg", this,
289 &FGAerodynamics::GetAlphaCLMax,
290 &FGAerodynamics::SetAlphaCLMax,
292 PropertyManager->Tie("aero/alpha-min-deg", this,
293 &FGAerodynamics::GetAlphaCLMin,
294 &FGAerodynamics::SetAlphaCLMin,
296 PropertyManager->Tie("aero/bi2vel", this,
297 &FGAerodynamics::GetBI2Vel);
298 PropertyManager->Tie("aero/ci2vel", this,
299 &FGAerodynamics::GetCI2Vel);
300 PropertyManager->Tie("aero/alpha-wing-rad", this,
301 &FGAerodynamics::GetAlphaW);
302 PropertyManager->Tie("systems/stall-warn-norm", this,
303 &FGAerodynamics::GetStallWarn);
304 PropertyManager->Tie("aero/stall-hyst-norm", this,
305 &FGAerodynamics::GetHysteresisParm);
308 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
310 void FGAerodynamics::bindModel(void)
313 FGPropertyManager* node;
314 string axis_node_name;
315 node = PropertyManager->GetNode("aero/buildup",true);
316 for (i=0;i<NAxes;i++) {
317 node = node->GetNode( string(AxisNames[i]),true );
318 for (j=0; j < Coeff[i].size(); j++) {
319 Coeff[i][j]->bind(node);
321 node = (FGPropertyManager*)node->getParent();
325 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
327 void FGAerodynamics::unbind(void)
331 PropertyManager->Untie("forces/fbx-aero-lbs");
332 PropertyManager->Untie("forces/fby-aero-lbs");
333 PropertyManager->Untie("forces/fbz-aero-lbs");
334 PropertyManager->Untie("moments/l-aero-lbsft");
335 PropertyManager->Untie("moments/m-aero-lbsft");
336 PropertyManager->Untie("moments/n-aero-lbsft");
337 PropertyManager->Untie("forces/fwx-aero-lbs");
338 PropertyManager->Untie("forces/fwy-aero-lbs");
339 PropertyManager->Untie("forces/fwz-aero-lbs");
340 PropertyManager->Untie("forces/lod-norm");
341 PropertyManager->Untie("aero/cl-squared-norm");
342 PropertyManager->Untie("aero/alpha-max-deg");
343 PropertyManager->Untie("aero/alpha-min-deg");
344 PropertyManager->Untie("aero/bi2vel");
345 PropertyManager->Untie("aero/ci2vel");
346 PropertyManager->Untie("aero/alpha-wing-rad");
347 PropertyManager->Untie("aero/stall-hyst-norm");
348 PropertyManager->Untie("systems/stall-warn-norm");
350 for ( i=0; i<NAxes; i++ ) {
351 for ( j=0; j < Coeff[i].size(); j++ ) {
352 Coeff[i][j]->unbind();
358 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
359 // The bitmasked value choices are as follows:
360 // unset: In this case (the default) JSBSim would only print
361 // out the normally expected messages, essentially echoing
362 // the config files as they are read. If the environment
363 // variable is not set, debug_lvl is set to 1 internally
364 // 0: This requests JSBSim not to output any messages
366 // 1: This value explicity requests the normal JSBSim
368 // 2: This value asks for a message to be printed out when
369 // a class is instantiated
370 // 4: When this value is set, a message is displayed when a
371 // FGModel object executes its Run() method
372 // 8: When this value is set, various runtime state variables
373 // are printed out periodically
374 // 16: When set various parameters are sanity checked and
375 // a message is printed out when they go out of bounds
377 void FGAerodynamics::Debug(int from)
379 if (debug_lvl <= 0) return;
381 if (debug_lvl & 1) { // Standard console startup message output
382 if (from == 0) { // Constructor
386 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
387 if (from == 0) cout << "Instantiated: FGAerodynamics" << endl;
388 if (from == 1) cout << "Destroyed: FGAerodynamics" << endl;
390 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
392 if (debug_lvl & 8 ) { // Runtime state variables
394 if (debug_lvl & 16) { // Sanity checking
396 if (debug_lvl & 64) {
397 if (from == 0) { // Constructor
398 cout << IdSrc << endl;
399 cout << IdHdr << endl;
404 } // namespace JSBSim