1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
7 --------- Copyright (C) 1999 Anthony K. Peden (apeden@earthlink.net) ---------
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
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
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.
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.
28 --------------------------------------------------------------------------------
31 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
33 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
36 # pragma warning (disable : 4786)
42 #include <FGFDMExec.h>
43 #include <models/FGAtmosphere.h>
44 #include "FGInitialCondition.h"
45 #include "FGTrimAxis.h"
46 #include <models/FGAircraft.h>
47 #include <models/FGPropulsion.h>
48 #include <models/FGAerodynamics.h>
53 static const char *IdSrc = "$Id$";
54 static const char *IdHdr = ID_TRIMAXIS;
56 /*****************************************************************************/
58 FGTrimAxis::FGTrimAxis(FGFDMExec* fdex, FGInitialCondition* ic, State st,
67 its_to_stable_value=0;
69 total_stability_iterations=0;
75 case tUdot: tolerance = DEFAULT_TOLERANCE; break;
76 case tVdot: tolerance = DEFAULT_TOLERANCE; break;
77 case tWdot: tolerance = DEFAULT_TOLERANCE; break;
78 case tQdot: tolerance = DEFAULT_TOLERANCE / 10; break;
79 case tPdot: tolerance = DEFAULT_TOLERANCE / 10; break;
80 case tRdot: tolerance = DEFAULT_TOLERANCE / 10; break;
81 case tHmgt: tolerance = 0.01; break;
82 case tNlf: state_target=1.0; tolerance = 1E-5; break;
94 control_min=-30*degtorad;
95 control_max=30*degtorad;
96 control_convert=radtodeg;
99 control_min=fdmex->GetAerodynamics()->GetAlphaCLMin();
100 control_max=fdmex->GetAerodynamics()->GetAlphaCLMax();
101 if(control_max <= control_min) {
102 control_max=20*degtorad;
103 control_min=-5*degtorad;
105 control_value= (control_min+control_max)/2;
106 control_convert=radtodeg;
107 solver_eps=tolerance/100;
117 state_convert=radtodeg;
118 solver_eps=tolerance/100;
123 control_value=fdmex->GetPropagate()->GetDistanceAGL();
124 solver_eps=tolerance/100;
127 control_min=fdmex->GetPropagate()->GetEuler(eTht) - 5*degtorad;
128 control_max=fdmex->GetPropagate()->GetEuler(eTht) + 5*degtorad;
129 state_convert=radtodeg;
132 control_min=fdmex->GetPropagate()->GetEuler(ePhi) - 30*degtorad;
133 control_max=fdmex->GetPropagate()->GetEuler(ePhi) + 30*degtorad;
134 state_convert=radtodeg;
135 control_convert=radtodeg;
138 solver_eps=tolerance/100;
139 control_min=-80*degtorad;
140 control_max=80*degtorad;
141 control_convert=radtodeg;
144 control_min=fdmex->GetPropagate()->GetEuler(ePsi) - 30*degtorad;
145 control_max=fdmex->GetPropagate()->GetEuler(ePsi) + 30*degtorad;
146 state_convert=radtodeg;
154 /*****************************************************************************/
156 FGTrimAxis::~FGTrimAxis(void)
161 /*****************************************************************************/
163 void FGTrimAxis::getState(void) {
165 case tUdot: state_value=fdmex->GetPropagate()->GetUVWdot(1)-state_target; break;
166 case tVdot: state_value=fdmex->GetPropagate()->GetUVWdot(2)-state_target; break;
167 case tWdot: state_value=fdmex->GetPropagate()->GetUVWdot(3)-state_target; break;
168 case tQdot: state_value=fdmex->GetPropagate()->GetPQRdot(2)-state_target;break;
169 case tPdot: state_value=fdmex->GetPropagate()->GetPQRdot(1)-state_target; break;
170 case tRdot: state_value=fdmex->GetPropagate()->GetPQRdot(3)-state_target; break;
171 case tHmgt: state_value=computeHmgt()-state_target; break;
172 case tNlf: state_value=fdmex->GetAircraft()->GetNlf()-state_target; break;
177 /*****************************************************************************/
179 //States are not settable
181 void FGTrimAxis::getControl(void) {
183 case tThrottle: control_value=fdmex->GetFCS()->GetThrottleCmd(0); break;
184 case tBeta: control_value=fdmex->GetAuxiliary()->Getbeta(); break;
185 case tAlpha: control_value=fdmex->GetAuxiliary()->Getalpha(); break;
186 case tPitchTrim: control_value=fdmex->GetFCS() -> GetPitchTrimCmd(); break;
187 case tElevator: control_value=fdmex->GetFCS() -> GetDeCmd(); break;
189 case tAileron: control_value=fdmex->GetFCS() -> GetDaCmd(); break;
191 case tRudder: control_value=fdmex->GetFCS() -> GetDrCmd(); break;
192 case tAltAGL: control_value=fdmex->GetPropagate()->GetDistanceAGL();break;
193 case tTheta: control_value=fdmex->GetPropagate()->GetEuler(eTht); break;
194 case tPhi: control_value=fdmex->GetPropagate()->GetEuler(ePhi); break;
195 case tGamma: control_value=fdmex->GetAuxiliary()->GetGamma();break;
196 case tHeading: control_value=fdmex->GetPropagate()->GetEuler(ePsi); break;
200 /*****************************************************************************/
202 double FGTrimAxis::computeHmgt(void) {
205 diff = fdmex->GetPropagate()->GetEuler(ePsi) -
206 fdmex->GetAuxiliary()->GetGroundTrack();
209 return (diff + 2*M_PI);
210 } else if( diff > M_PI ) {
211 return (diff - 2*M_PI);
218 /*****************************************************************************/
221 void FGTrimAxis::setControl(void) {
223 case tThrottle: setThrottlesPct(); break;
224 case tBeta: fgic->SetBetaRadIC(control_value); break;
225 case tAlpha: fgic->SetAlphaRadIC(control_value); break;
226 case tPitchTrim: fdmex->GetFCS()->SetPitchTrimCmd(control_value); break;
227 case tElevator: fdmex->GetFCS()->SetDeCmd(control_value); break;
229 case tAileron: fdmex->GetFCS()->SetDaCmd(control_value); break;
231 case tRudder: fdmex->GetFCS()->SetDrCmd(control_value); break;
232 case tAltAGL: fgic->SetAltitudeAGLFtIC(control_value); break;
233 case tTheta: fgic->SetThetaRadIC(control_value); break;
234 case tPhi: fgic->SetPhiRadIC(control_value); break;
235 case tGamma: fgic->SetFlightPathAngleRadIC(control_value); break;
236 case tHeading: fgic->SetPsiRadIC(control_value); break;
244 /*****************************************************************************/
246 // the aircraft center of rotation is no longer the cg once the gear
247 // contact the ground so the altitude needs to be changed when pitch
248 // and roll angle are adjusted. Instead of attempting to calculate the
249 // new center of rotation, pick a gear unit as a reference and use its
250 // location vector to calculate the new height change. i.e. new altitude =
251 // earth z component of that vector (which is in body axes )
252 void FGTrimAxis::SetThetaOnGround(double ff) {
255 // favor an off-center unit so that the same one can be used for both
256 // pitch and roll. An on-center unit is used (for pitch)if that's all
257 // that's in contact with the ground.
258 i=0; ref=-1; center=-1;
259 while( (ref < 0) && (i < fdmex->GetGroundReactions()->GetNumGearUnits()) ) {
260 if(fdmex->GetGroundReactions()->GetGearUnit(i)->GetWOW()) {
261 if(fabs(fdmex->GetGroundReactions()->GetGearUnit(i)->GetBodyLocation(2)) > 0.01)
268 if((ref < 0) && (center >= 0)) {
271 cout << "SetThetaOnGround ref gear: " << ref << endl;
273 double sp = fdmex->GetPropagate()->GetSinEuler(ePhi);
274 double cp = fdmex->GetPropagate()->GetCosEuler(ePhi);
275 double lx = fdmex->GetGroundReactions()->GetGearUnit(ref)->GetBodyLocation(1);
276 double ly = fdmex->GetGroundReactions()->GetGearUnit(ref)->GetBodyLocation(2);
277 double lz = fdmex->GetGroundReactions()->GetGearUnit(ref)->GetBodyLocation(3);
278 double hagl = -1*lx*sin(ff) +
282 fgic->SetAltitudeAGLFtIC(hagl);
283 cout << "SetThetaOnGround new alt: " << hagl << endl;
285 fgic->SetThetaRadIC(ff);
286 cout << "SetThetaOnGround new theta: " << ff << endl;
289 /*****************************************************************************/
291 bool FGTrimAxis::initTheta(void) {
295 double zAft,zForward,zDiff,theta;
296 double xAft,xForward,xDiff;
300 saveAlt=fgic->GetAltitudeAGLFtIC();
301 fgic->SetAltitudeAGLFtIC(100);
304 N=fdmex->GetGroundReactions()->GetNumGearUnits();
306 //find the first wheel unit forward of the cg
307 //the list is short so a simple linear search is fine
308 for( i=0; i<N; i++ ) {
309 if(fdmex->GetGroundReactions()->GetGearUnit(i)->GetBodyLocation(1) > 0 ) {
314 //now find the first wheel unit aft of the cg
315 for( i=0; i<N; i++ ) {
316 if(fdmex->GetGroundReactions()->GetGearUnit(i)->GetBodyLocation(1) < 0 ) {
322 // now adjust theta till the wheels are the same distance from the ground
323 xAft=fdmex->GetGroundReactions()->GetGearUnit(iAft)->GetBodyLocation(1);
324 xForward=fdmex->GetGroundReactions()->GetGearUnit(iForward)->GetBodyLocation(1);
325 xDiff = xForward - xAft;
326 zAft=fdmex->GetGroundReactions()->GetGearUnit(iAft)->GetLocalGear(3);
327 zForward=fdmex->GetGroundReactions()->GetGearUnit(iForward)->GetLocalGear(3);
328 zDiff = zForward - zAft;
330 theta=fgic->GetThetaDegIC();
331 while(!level && (i < 100)) {
332 theta+=radtodeg*atan(zDiff/xDiff);
333 fgic->SetThetaDegIC(theta);
335 zAft=fdmex->GetGroundReactions()->GetGearUnit(iAft)->GetLocalGear(3);
336 zForward=fdmex->GetGroundReactions()->GetGearUnit(iForward)->GetLocalGear(3);
337 zDiff = zForward - zAft;
338 //cout << endl << theta << " " << zDiff << endl;
339 //cout << "0: " << fdmex->GetGroundReactions()->GetGearUnit(0)->GetLocalGear() << endl;
340 //cout << "1: " << fdmex->GetGroundReactions()->GetGearUnit(1)->GetLocalGear() << endl;
341 if(fabs(zDiff ) < 0.1)
347 cout << " Initial Theta: " << fdmex->GetPropagate()->GetEuler(eTht)*radtodeg << endl;
348 cout << " Used gear unit " << iAft << " as aft and " << iForward << " as forward" << endl;
350 control_min=(theta+5)*degtorad;
351 control_max=(theta-5)*degtorad;
352 fgic->SetAltitudeAGLFtIC(saveAlt);
359 /*****************************************************************************/
361 void FGTrimAxis::SetPhiOnGround(double ff) {
365 //must have an off-center unit here
366 while ( (ref < 0) && (i < fdmex->GetGroundReactions()->GetNumGearUnits()) ) {
367 if ( (fdmex->GetGroundReactions()->GetGearUnit(i)->GetWOW()) &&
368 (fabs(fdmex->GetGroundReactions()->GetGearUnit(i)->GetBodyLocation(2)) > 0.01))
373 double st = fdmex->GetPropagate()->GetSinEuler(eTht);
374 double ct = fdmex->GetPropagate()->GetCosEuler(eTht);
375 double lx = fdmex->GetGroundReactions()->GetGearUnit(ref)->GetBodyLocation(1);
376 double ly = fdmex->GetGroundReactions()->GetGearUnit(ref)->GetBodyLocation(2);
377 double lz = fdmex->GetGroundReactions()->GetGearUnit(ref)->GetBodyLocation(3);
378 double hagl = -1*lx*st +
382 fgic->SetAltitudeAGLFtIC(hagl);
384 fgic->SetPhiRadIC(ff);
388 /*****************************************************************************/
390 void FGTrimAxis::Run(void) {
392 double last_state_value;
395 //cout << "FGTrimAxis::Run: " << control_value << endl;
400 last_state_value=state_value;
404 if((fabs(last_state_value - state_value) < tolerance) || (i >= 100) )
409 its_to_stable_value=i;
410 total_stability_iterations+=its_to_stable_value;
414 /*****************************************************************************/
416 void FGTrimAxis::setThrottlesPct(void) {
418 for(unsigned i=0;i<fdmex->GetPropulsion()->GetNumEngines();i++) {
419 tMin=fdmex->GetPropulsion()->GetEngine(i)->GetThrottleMin();
420 tMax=fdmex->GetPropulsion()->GetEngine(i)->GetThrottleMax();
421 //cout << "setThrottlespct: " << i << ", " << control_min << ", " << control_max << ", " << control_value;
422 fdmex->GetFCS()->SetThrottleCmd(i,tMin+control_value*(tMax-tMin));
423 //cout << "setThrottlespct: " << fdmex->GetFCS()->GetThrottleCmd(i) << endl;
424 fdmex->RunIC(); //apply throttle change
425 fdmex->GetPropulsion()->GetSteadyState();
429 /*****************************************************************************/
431 void FGTrimAxis::AxisReport(void) {
435 sprintf(out," %20s: %6.2f %5s: %9.2e Tolerance: %3.0e",
436 GetControlName().c_str(), GetControl()*control_convert,
437 GetStateName().c_str(), GetState()+state_target, GetTolerance());
440 if( fabs(GetState()+state_target) < fabs(GetTolerance()) )
441 cout << " Passed" << endl;
443 cout << " Failed" << endl;
446 /*****************************************************************************/
448 double FGTrimAxis::GetAvgStability( void ) {
449 if(total_iterations > 0) {
450 return double(total_stability_iterations)/double(total_iterations);
455 /*****************************************************************************/
456 // The bitmasked value choices are as follows:
457 // unset: In this case (the default) JSBSim would only print
458 // out the normally expected messages, essentially echoing
459 // the config files as they are read. If the environment
460 // variable is not set, debug_lvl is set to 1 internally
461 // 0: This requests JSBSim not to output any messages
463 // 1: This value explicity requests the normal JSBSim
465 // 2: This value asks for a message to be printed out when
466 // a class is instantiated
467 // 4: When this value is set, a message is displayed when a
468 // FGModel object executes its Run() method
469 // 8: When this value is set, various runtime state variables
470 // are printed out periodically
471 // 16: When set various parameters are sanity checked and
472 // a message is printed out when they go out of bounds
474 void FGTrimAxis::Debug(int from)
477 if (debug_lvl <= 0) return;
478 if (debug_lvl & 1 ) { // Standard console startup message output
479 if (from == 0) { // Constructor
483 if (debug_lvl & 2 ) { // Instantiation/Destruction notification
484 if (from == 0) cout << "Instantiated: FGTrimAxis" << endl;
485 if (from == 1) cout << "Destroyed: FGTrimAxis" << endl;
487 if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
489 if (debug_lvl & 8 ) { // Runtime state variables
491 if (debug_lvl & 16) { // Sanity checking
493 if (debug_lvl & 64) {
494 if (from == 0) { // Constructor
495 cout << IdSrc << endl;
496 cout << IdHdr << endl;