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1 // JSBsim.cxx -- interface to the JSBsim flight model
2 //
3 // Written by Curtis Olson, started February 1999.
4 //
5 // Copyright (C) 1999  Curtis L. Olson  - curt@flightgear.org
6 //
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU Lesser General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
11 //
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 // Lesser General Public License for more details.
16 //
17 // You should have received a copy of the GNU Lesser General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 //
21 // $Id: JSBSim.cxx,v 1.64 2010/10/31 04:49:25 jberndt Exp $
22
23
24 #ifdef HAVE_CONFIG_H
25 #  include <config.h>
26 #endif
27
28 #include <simgear/compiler.h>
29
30 #include <stdio.h>    //    size_t
31 #include <string>
32
33 #include <simgear/constants.h>
34 #include <simgear/debug/logstream.hxx>
35 #include <simgear/math/sg_geodesy.hxx>
36 #include <simgear/misc/sg_path.hxx>
37 #include <simgear/structure/commands.hxx>
38
39 #include <FDM/flight.hxx>
40
41 #include <Aircraft/controls.hxx>
42 #include <Main/globals.hxx>
43 #include <Main/fg_props.hxx>
44
45 #include "JSBSim.hxx"
46 #include <FDM/JSBSim/FGFDMExec.h>
47 #include <FDM/JSBSim/FGJSBBase.h>
48 #include <FDM/JSBSim/initialization/FGInitialCondition.h>
49 #include <FDM/JSBSim/initialization/FGTrim.h>
50 #include <FDM/JSBSim/models/FGModel.h>
51 #include <FDM/JSBSim/models/FGAircraft.h>
52 #include <FDM/JSBSim/models/FGFCS.h>
53 #include <FDM/JSBSim/models/FGPropagate.h>
54 #include <FDM/JSBSim/models/FGAuxiliary.h>
55 #include <FDM/JSBSim/models/FGInertial.h>
56 #include <FDM/JSBSim/models/FGAtmosphere.h>
57 #include <FDM/JSBSim/models/FGMassBalance.h>
58 #include <FDM/JSBSim/models/FGAerodynamics.h>
59 #include <FDM/JSBSim/models/FGLGear.h>
60 #include <FDM/JSBSim/models/FGGroundReactions.h>
61 #include <FDM/JSBSim/models/FGPropulsion.h>
62 #include <FDM/JSBSim/models/propulsion/FGEngine.h>
63 #include <FDM/JSBSim/models/propulsion/FGPiston.h>
64 #include <FDM/JSBSim/models/propulsion/FGTurbine.h>
65 #include <FDM/JSBSim/models/propulsion/FGTurboProp.h>
66 #include <FDM/JSBSim/models/propulsion/FGRocket.h>
67 #include <FDM/JSBSim/models/propulsion/FGElectric.h>
68 #include <FDM/JSBSim/models/propulsion/FGNozzle.h>
69 #include <FDM/JSBSim/models/propulsion/FGPropeller.h>
70 #include <FDM/JSBSim/models/propulsion/FGRotor.h>
71 #include <FDM/JSBSim/models/propulsion/FGTank.h>
72 #include <FDM/JSBSim/input_output/FGPropertyManager.h>
73 #include <FDM/JSBSim/input_output/FGGroundCallback.h>
74
75 using namespace JSBSim;
76
77 static inline double
78 FMAX (double a, double b)
79 {
80   return a > b ? a : b;
81 }
82
83 class FGFSGroundCallback : public FGGroundCallback {
84 public:
85   FGFSGroundCallback(FGJSBsim* ifc) : mInterface(ifc) {}
86   virtual ~FGFSGroundCallback() {}
87
88   /** Get the altitude above sea level dependent on the location. */
89   virtual double GetAltitude(const FGLocation& l) const {
90     double pt[3] = { SG_FEET_TO_METER*l(eX),
91                      SG_FEET_TO_METER*l(eY),
92                      SG_FEET_TO_METER*l(eZ) };
93     double lat, lon, alt;
94     sgCartToGeod( pt, &lat, &lon, &alt);
95     return alt * SG_METER_TO_FEET;
96   }
97
98   /** Compute the altitude above ground. */
99   virtual double GetAGLevel(double t, const FGLocation& l,
100                             FGLocation& cont, FGColumnVector3& n,
101                             FGColumnVector3& v, FGColumnVector3& w) const {
102     double loc_cart[3] = { l(eX), l(eY), l(eZ) };
103     double contact[3], normal[3], vel[3], angularVel[3], agl = 0;
104     mInterface->get_agl_ft(t, loc_cart, SG_METER_TO_FEET*2, contact, normal,
105                            vel, angularVel, &agl);
106     n = FGColumnVector3( normal[0], normal[1], normal[2] );
107     v = FGColumnVector3( vel[0], vel[1], vel[2] );
108     w = FGColumnVector3( angularVel[0], angularVel[1], angularVel[2] );
109     cont = FGColumnVector3( contact[0], contact[1], contact[2] );
110     return agl;
111   }
112 private:
113   FGJSBsim* mInterface;
114 };
115
116 /******************************************************************************/
117
118 FGJSBsim::FGJSBsim( double dt )
119   : FGInterface(dt), got_wire(false)
120 {
121     bool result;
122                                 // Set up the debugging level
123                                 // FIXME: this will not respond to
124                                 // runtime changes
125
126                                 // if flight is excluded, don't bother
127     if ((logbuf::get_log_classes() & SG_FLIGHT) != 0) {
128
129                                 // do a rough-and-ready mapping to
130                                 // the levels documented in FGFDMExec.h
131         switch (logbuf::get_log_priority()) {
132         case SG_BULK:
133             FGJSBBase::debug_lvl = 0x1f;
134             break;
135         case SG_DEBUG:
136             FGJSBBase::debug_lvl = 0x0f;
137         case SG_INFO:
138             FGJSBBase::debug_lvl = 0x01;
139             break;
140         case SG_WARN:
141         case SG_ALERT:
142             FGJSBBase::debug_lvl = 0x00;
143             break;
144         }
145     }
146
147     fdmex = new FGFDMExec( (FGPropertyManager*)globals->get_props() );
148
149     // Register ground callback.
150     fdmex->SetGroundCallback( new FGFSGroundCallback(this) );
151
152     Atmosphere      = fdmex->GetAtmosphere();
153     FCS             = fdmex->GetFCS();
154     MassBalance     = fdmex->GetMassBalance();
155     Propulsion      = fdmex->GetPropulsion();
156     Aircraft        = fdmex->GetAircraft();
157     Propagate        = fdmex->GetPropagate();
158     Auxiliary       = fdmex->GetAuxiliary();
159     Inertial        = fdmex->GetInertial();
160     Aerodynamics    = fdmex->GetAerodynamics();
161     GroundReactions = fdmex->GetGroundReactions();
162
163     fgic=fdmex->GetIC();
164     needTrim=true;
165
166     SGPath aircraft_path( fgGetString("/sim/aircraft-dir") );
167
168     SGPath engine_path( fgGetString("/sim/aircraft-dir") );
169     engine_path.append( "Engine" );
170
171     SGPath systems_path( fgGetString("/sim/aircraft-dir") );
172     systems_path.append( "Systems" );
173
174 // deprecate sim-time-sec for simulation/sim-time-sec
175 // remove alias with increased configuration file version number (2.1 or later)
176     SGPropertyNode * node = fgGetNode("/fdm/jsbsim/simulation/sim-time-sec");
177     fgGetNode("/fdm/jsbsim/sim-time-sec", true)->alias( node );
178 // end of sim-time-sec deprecation patch
179
180     fdmex->Setdt( dt );
181
182     result = fdmex->LoadModel( aircraft_path.str(),
183                                engine_path.str(),
184                                systems_path.str(),
185                                fgGetString("/sim/aero"), false );
186
187     if (result) {
188       SG_LOG( SG_FLIGHT, SG_INFO, "  loaded aero.");
189     } else {
190       SG_LOG( SG_FLIGHT, SG_INFO,
191               "  aero does not exist (you may have mis-typed the name).");
192       throw(-1);
193     }
194
195     SG_LOG( SG_FLIGHT, SG_INFO, "" );
196     SG_LOG( SG_FLIGHT, SG_INFO, "" );
197     SG_LOG( SG_FLIGHT, SG_INFO, "After loading aero definition file ..." );
198
199     int Neng = Propulsion->GetNumEngines();
200     SG_LOG( SG_FLIGHT, SG_INFO, "num engines = " << Neng );
201
202     if ( GroundReactions->GetNumGearUnits() <= 0 ) {
203         SG_LOG( SG_FLIGHT, SG_ALERT, "num gear units = "
204                 << GroundReactions->GetNumGearUnits() );
205         SG_LOG( SG_FLIGHT, SG_ALERT, "This is a very bad thing because with 0 gear units, the ground trimming");
206         SG_LOG( SG_FLIGHT, SG_ALERT, "routine (coming up later in the code) will core dump.");
207         SG_LOG( SG_FLIGHT, SG_ALERT, "Halting the sim now, and hoping a solution will present itself soon!");
208         exit(-1);
209     }
210
211     init_gear();
212
213     // Set initial fuel levels if provided.
214     for (unsigned int i = 0; i < Propulsion->GetNumTanks(); i++) {
215       SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
216       if (node->getChild("level-gal_us", 0, false) != 0) {
217         Propulsion->GetTank(i)->SetContents(node->getDoubleValue("level-gal_us") * 6.6);
218       } else {
219         node->setDoubleValue("level-lbs", Propulsion->GetTank(i)->GetContents());
220         node->setDoubleValue("level-gal_us", Propulsion->GetTank(i)->GetContents() / 6.6);
221       }
222       node->setDoubleValue("capacity-gal_us",
223                            Propulsion->GetTank(i)->GetCapacity() / 6.6);
224     }
225     Propulsion->SetFuelFreeze((fgGetNode("/sim/freeze/fuel",true))->getBoolValue());
226
227     fgSetDouble("/fdm/trim/pitch-trim", FCS->GetPitchTrimCmd());
228     fgSetDouble("/fdm/trim/throttle",   FCS->GetThrottleCmd(0));
229     fgSetDouble("/fdm/trim/aileron",    FCS->GetDaCmd());
230     fgSetDouble("/fdm/trim/rudder",     FCS->GetDrCmd());
231
232     startup_trim = fgGetNode("/sim/presets/trim", true);
233
234     trimmed = fgGetNode("/fdm/trim/trimmed", true);
235     trimmed->setBoolValue(false);
236
237     pitch_trim = fgGetNode("/fdm/trim/pitch-trim", true );
238     throttle_trim = fgGetNode("/fdm/trim/throttle", true );
239     aileron_trim = fgGetNode("/fdm/trim/aileron", true );
240     rudder_trim = fgGetNode("/fdm/trim/rudder", true );
241
242     stall_warning = fgGetNode("/sim/alarms/stall-warning",true);
243     stall_warning->setDoubleValue(0);
244
245
246     flap_pos_pct=fgGetNode("/surface-positions/flap-pos-norm",true);
247     elevator_pos_pct=fgGetNode("/surface-positions/elevator-pos-norm",true);
248     left_aileron_pos_pct
249         =fgGetNode("/surface-positions/left-aileron-pos-norm",true);
250     right_aileron_pos_pct
251         =fgGetNode("/surface-positions/right-aileron-pos-norm",true);
252     rudder_pos_pct=fgGetNode("/surface-positions/rudder-pos-norm",true);
253     speedbrake_pos_pct
254         =fgGetNode("/surface-positions/speedbrake-pos-norm",true);
255     spoilers_pos_pct=fgGetNode("/surface-positions/spoilers-pos-norm",true);
256     tailhook_pos_pct=fgGetNode("/gear/tailhook/position-norm",true);
257     wing_fold_pos_pct=fgGetNode("surface-positions/wing-fold-pos-norm",true);
258
259     elevator_pos_pct->setDoubleValue(0);
260     left_aileron_pos_pct->setDoubleValue(0);
261     right_aileron_pos_pct->setDoubleValue(0);
262     rudder_pos_pct->setDoubleValue(0);
263     flap_pos_pct->setDoubleValue(0);
264     speedbrake_pos_pct->setDoubleValue(0);
265     spoilers_pos_pct->setDoubleValue(0);
266
267     ab_brake_engaged = fgGetNode("/autopilot/autobrake/engaged", true);
268     ab_brake_left_pct = fgGetNode("/autopilot/autobrake/brake-left-output", true);
269     ab_brake_right_pct = fgGetNode("/autopilot/autobrake/brake-right-output", true);
270     
271     temperature = fgGetNode("/environment/temperature-degc",true);
272     pressure = fgGetNode("/environment/pressure-inhg",true);
273     density = fgGetNode("/environment/density-slugft3",true);
274     turbulence_gain = fgGetNode("/environment/turbulence/magnitude-norm",true);
275     turbulence_rate = fgGetNode("/environment/turbulence/rate-hz",true);
276
277     wind_from_north= fgGetNode("/environment/wind-from-north-fps",true);
278     wind_from_east = fgGetNode("/environment/wind-from-east-fps" ,true);
279     wind_from_down = fgGetNode("/environment/wind-from-down-fps" ,true);
280
281     slaved = fgGetNode("/sim/slaved/enabled", true);
282
283     for (unsigned int i = 0; i < Propulsion->GetNumEngines(); i++) {
284       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
285       Propulsion->GetEngine(i)->GetThruster()->SetRPM(node->getDoubleValue("rpm") /
286                      Propulsion->GetEngine(i)->GetThruster()->GetGearRatio());
287     }
288
289     hook_root_struct = FGColumnVector3(
290         fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-offset-x-in", 196),
291         fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-offset-y-in", 0),
292         fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-offset-z-in", -16));
293
294     crashed = false;
295 }
296
297 /******************************************************************************/
298 FGJSBsim::~FGJSBsim(void)
299 {
300   delete fdmex;
301 }
302
303 /******************************************************************************/
304
305 // Initialize the JSBsim flight model, dt is the time increment for
306 // each subsequent iteration through the EOM
307
308 void FGJSBsim::init()
309 {
310     SG_LOG( SG_FLIGHT, SG_INFO, "Starting and initializing JSBsim" );
311
312     // Explicitly call the superclass's
313     // init method first.
314
315     if (fgGetBool("/environment/params/control-fdm-atmosphere")) {
316       Atmosphere->UseExternal();
317       Atmosphere->SetExTemperature(
318                   9.0/5.0*(temperature->getDoubleValue()+273.15) );
319       Atmosphere->SetExPressure(pressure->getDoubleValue()*70.726566);
320       Atmosphere->SetExDensity(density->getDoubleValue());
321       Atmosphere->SetTurbType(FGAtmosphere::ttCulp);
322       Atmosphere->SetTurbGain(turbulence_gain->getDoubleValue());
323       Atmosphere->SetTurbRate(turbulence_rate->getDoubleValue());
324
325     } else {
326       Atmosphere->UseInternal();
327     }
328
329     fgic->SetVNorthFpsIC( -wind_from_north->getDoubleValue() );
330     fgic->SetVEastFpsIC( -wind_from_east->getDoubleValue() );
331     fgic->SetVDownFpsIC( -wind_from_down->getDoubleValue() );
332
333     //Atmosphere->SetExTemperature(get_Static_temperature());
334     //Atmosphere->SetExPressure(get_Static_pressure());
335     //Atmosphere->SetExDensity(get_Density());
336     SG_LOG(SG_FLIGHT,SG_INFO,"T,p,rho: " << fdmex->GetAtmosphere()->GetTemperature()
337      << ", " << fdmex->GetAtmosphere()->GetPressure()
338      << ", " << fdmex->GetAtmosphere()->GetDensity() );
339
340 // deprecate egt_degf for egt-degf to have consistent naming
341 // TODO: raise log-level to ALERT in summer 2010, 
342 // remove alias in fall 2010, 
343 // remove this code in winter 2010
344     for (unsigned int i=0; i < Propulsion->GetNumEngines(); i++) {
345       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
346       SGPropertyNode * egtn = node->getNode( "egt_degf" );
347       if( egtn != NULL ) {
348         SG_LOG(SG_FLIGHT,SG_WARN,
349                "Aircraft uses deprecated node egt_degf. Please upgrade to egt-degf");
350         node->getNode("egt-degf", true)->alias( egtn );
351       }
352     }
353 // end of egt_degf deprecation patch
354
355     if (fgGetBool("/sim/presets/running")) {
356           for (unsigned int i=0; i < Propulsion->GetNumEngines(); i++) {
357             SGPropertyNode * node = fgGetNode("engines/engine", i, true);
358             node->setBoolValue("running", true);
359             Propulsion->GetEngine(i)->SetRunning(true);
360           }
361     }
362
363     FCS->SetDfPos( ofNorm, globals->get_controls()->get_flaps() );
364
365     common_init();
366
367     copy_to_JSBsim();
368     fdmex->RunIC();     //loop JSBSim once w/o integrating
369     copy_from_JSBsim(); //update the bus
370
371     SG_LOG( SG_FLIGHT, SG_INFO, "  Initialized JSBSim with:" );
372
373     switch(fgic->GetSpeedSet()) {
374     case setned:
375         SG_LOG(SG_FLIGHT,SG_INFO, "  Vn,Ve,Vd= "
376                << Propagate->GetVel(FGJSBBase::eNorth) << ", "
377                << Propagate->GetVel(FGJSBBase::eEast) << ", "
378                << Propagate->GetVel(FGJSBBase::eDown) << " ft/s");
379     break;
380     case setuvw:
381         SG_LOG(SG_FLIGHT,SG_INFO, "  U,V,W= "
382                << Propagate->GetUVW(1) << ", "
383                << Propagate->GetUVW(2) << ", "
384                << Propagate->GetUVW(3) << " ft/s");
385     break;
386     case setmach:
387         SG_LOG(SG_FLIGHT,SG_INFO, "  Mach: "
388                << Auxiliary->GetMach() );
389     break;
390     case setvc:
391     default:
392         SG_LOG(SG_FLIGHT,SG_INFO, "  Indicated Airspeed: "
393                << Auxiliary->GetVcalibratedKTS() << " knots" );
394     break;
395     }
396
397     stall_warning->setDoubleValue(0);
398
399     SG_LOG( SG_FLIGHT, SG_INFO, "  Bank Angle: "
400             << Propagate->GetEuler(FGJSBBase::ePhi)*RADTODEG << " deg" );
401     SG_LOG( SG_FLIGHT, SG_INFO, "  Pitch Angle: "
402             << Propagate->GetEuler(FGJSBBase::eTht)*RADTODEG << " deg" );
403     SG_LOG( SG_FLIGHT, SG_INFO, "  True Heading: "
404             << Propagate->GetEuler(FGJSBBase::ePsi)*RADTODEG << " deg" );
405     SG_LOG( SG_FLIGHT, SG_INFO, "  Latitude: "
406             << Propagate->GetLocation().GetLatitudeDeg() << " deg" );
407     SG_LOG( SG_FLIGHT, SG_INFO, "  Longitude: "
408             << Propagate->GetLocation().GetLongitudeDeg() << " deg" );
409     SG_LOG( SG_FLIGHT, SG_INFO, "  Altitude: "
410             << Propagate->GetAltitudeASL() << " feet" );
411     SG_LOG( SG_FLIGHT, SG_INFO, "  loaded initial conditions" );
412
413     SG_LOG( SG_FLIGHT, SG_INFO, "  set dt" );
414
415     SG_LOG( SG_FLIGHT, SG_INFO, "Finished initializing JSBSim" );
416
417     SG_LOG( SG_FLIGHT, SG_INFO, "FGControls::get_gear_down()= " <<
418                                   globals->get_controls()->get_gear_down() );
419 }
420
421 /******************************************************************************/
422
423 // Run an iteration of the EOM (equations of motion)
424
425 void FGJSBsim::update( double dt )
426 {
427     if(crashed) {
428       if(!fgGetBool("/sim/crashed"))
429         fgSetBool("/sim/crashed", true);
430       return;
431     }
432
433     if (is_suspended())
434       return;
435
436     int multiloop = _calc_multiloop(dt);
437
438     int i;
439
440     // Compute the radius of the aircraft. That is the radius of a ball
441     // where all gear units are in. At the moment it is at least 10ft ...
442     double acrad = 10.0;
443     int n_gears = GroundReactions->GetNumGearUnits();
444     for (i=0; i<n_gears; ++i) {
445       FGColumnVector3 bl = GroundReactions->GetGearUnit(i)->GetBodyLocation();
446       double r = bl.Magnitude();
447       if (acrad < r)
448         acrad = r;
449     }
450
451     // Compute the potential movement of this aircraft and query for the
452     // ground in this area.
453     double groundCacheRadius = acrad + 2*dt*Propagate->GetUVW().Magnitude();
454     double alt, slr, lat, lon;
455     FGLocation cart = Auxiliary->GetLocationVRP();
456     if ( needTrim && startup_trim->getBoolValue() ) {
457       alt = fgic->GetAltitudeASLFtIC();
458       slr = fgic->GetSeaLevelRadiusFtIC();
459       lat = fgic->GetLatitudeDegIC() * SGD_DEGREES_TO_RADIANS;
460       lon = fgic->GetLongitudeDegIC() * SGD_DEGREES_TO_RADIANS;
461       cart = FGLocation(lon, lat, alt+slr);
462     }
463     double cart_pos[3] = { cart(1), cart(2), cart(3) };
464     double t0 = fdmex->GetSimTime();
465     bool cache_ok = prepare_ground_cache_ft( t0, t0 + dt, cart_pos,
466                                              groundCacheRadius );
467     if (!cache_ok) {
468       SG_LOG(SG_FLIGHT, SG_WARN,
469              "FGInterface is being called without scenery below the aircraft!");
470
471       alt = fgic->GetAltitudeASLFtIC();
472       SG_LOG(SG_FLIGHT, SG_WARN, "altitude         = " << alt);
473
474       slr = fgic->GetSeaLevelRadiusFtIC();
475       SG_LOG(SG_FLIGHT, SG_WARN, "sea level radius = " << slr);
476
477       lat = fgic->GetLatitudeDegIC() * SGD_DEGREES_TO_RADIANS;
478       SG_LOG(SG_FLIGHT, SG_WARN, "latitude         = " << lat);
479
480       lon = fgic->GetLongitudeDegIC() * SGD_DEGREES_TO_RADIANS;
481       SG_LOG(SG_FLIGHT, SG_WARN, "longitude        = " << lon);
482       //return;
483     }
484
485     copy_to_JSBsim();
486
487     trimmed->setBoolValue(false);
488
489     if ( needTrim ) {
490       if ( startup_trim->getBoolValue() ) {
491         double contact[3], d[3], vel[3], agl;
492         get_agl_ft(fdmex->GetSimTime(), cart_pos, SG_METER_TO_FEET*2, contact,
493                    d, vel, d, &agl);
494         double terrain_alt = sqrt(contact[0]*contact[0] + contact[1]*contact[1]
495              + contact[2]*contact[2]) - fgic->GetSeaLevelRadiusFtIC();
496
497         SG_LOG(SG_FLIGHT, SG_INFO,
498           "Ready to trim, terrain elevation is: "
499             << terrain_alt * SG_METER_TO_FEET );
500
501         if (fgGetBool("/sim/presets/onground")) {
502           FGColumnVector3 gndVelNED = cart.GetTec2l()
503                                     * FGColumnVector3(vel[0], vel[1], vel[2]);
504           fgic->SetVNorthFpsIC(gndVelNED(1));
505           fgic->SetVEastFpsIC(gndVelNED(2));
506           fgic->SetVDownFpsIC(gndVelNED(3));
507         }
508         fgic->SetTerrainElevationFtIC( terrain_alt );
509         do_trim();
510       } else {
511         fdmex->RunIC();  //apply any changes made through the set_ functions
512       }
513       needTrim = false;
514     }
515
516     for ( i=0; i < multiloop; i++ ) {
517       fdmex->Run();
518       update_external_forces(fdmex->GetSimTime() + i * fdmex->GetDeltaT());      
519     }
520
521     FGJSBBase::Message* msg;
522     while (msg = fdmex->ProcessNextMessage()) {
523 //      msg = fdmex->ProcessNextMessage();
524       switch (msg->type) {
525       case FGJSBBase::Message::eText:
526         if (msg->text == "Crash Detected: Simulation FREEZE.")
527           crashed = true;
528         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text );
529         break;
530       case FGJSBBase::Message::eBool:
531         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->bVal );
532         break;
533       case FGJSBBase::Message::eInteger:
534         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->iVal );
535         break;
536       case FGJSBBase::Message::eDouble:
537         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->dVal );
538         break;
539       default:
540         SG_LOG( SG_FLIGHT, SG_INFO, "Unrecognized message type." );
541         break;
542       }
543     }
544
545     // translate JSBsim back to FG structure so that the
546     // autopilot (and the rest of the sim can use the updated values
547     copy_from_JSBsim();
548 }
549
550 /******************************************************************************/
551
552 // Convert from the FGInterface struct to the JSBsim generic_ struct
553
554 bool FGJSBsim::copy_to_JSBsim()
555 {
556     double tmp;
557     unsigned int i;
558
559     // copy control positions into the JSBsim structure
560
561     FCS->SetDaCmd( globals->get_controls()->get_aileron());
562     FCS->SetRollTrimCmd( globals->get_controls()->get_aileron_trim() );
563     FCS->SetDeCmd( globals->get_controls()->get_elevator());
564     FCS->SetPitchTrimCmd( globals->get_controls()->get_elevator_trim() );
565     FCS->SetDrCmd( -globals->get_controls()->get_rudder() );
566     FCS->SetYawTrimCmd( -globals->get_controls()->get_rudder_trim() );
567     FCS->SetDsCmd( globals->get_controls()->get_rudder() );
568     FCS->SetDfCmd( globals->get_controls()->get_flaps() );
569     FCS->SetDsbCmd( globals->get_controls()->get_speedbrake() );
570     FCS->SetDspCmd( globals->get_controls()->get_spoilers() );
571
572         // Parking brake sets minimum braking
573         // level for mains.
574     double parking_brake = globals->get_controls()->get_brake_parking();
575     double left_brake = globals->get_controls()->get_brake_left();
576     double right_brake = globals->get_controls()->get_brake_right();
577     
578     if (ab_brake_engaged->getBoolValue()) {
579       left_brake = ab_brake_left_pct->getDoubleValue();
580       right_brake = ab_brake_right_pct->getDoubleValue(); 
581     }
582     
583     FCS->SetLBrake(FMAX(left_brake, parking_brake));
584     FCS->SetRBrake(FMAX(right_brake, parking_brake));
585     
586     
587     FCS->SetCBrake( 0.0 );
588     // FCS->SetCBrake( globals->get_controls()->get_brake(2) );
589
590     FCS->SetGearCmd( globals->get_controls()->get_gear_down());
591     for (i = 0; i < Propulsion->GetNumEngines(); i++) {
592       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
593
594       FCS->SetThrottleCmd(i, globals->get_controls()->get_throttle(i));
595       FCS->SetMixtureCmd(i, globals->get_controls()->get_mixture(i));
596       FCS->SetPropAdvanceCmd(i, globals->get_controls()->get_prop_advance(i));
597       FCS->SetFeatherCmd(i, globals->get_controls()->get_feather(i));
598
599       switch (Propulsion->GetEngine(i)->GetType()) {
600       case FGEngine::etPiston:
601         { // FGPiston code block
602         FGPiston* eng = (FGPiston*)Propulsion->GetEngine(i);
603         eng->SetMagnetos( globals->get_controls()->get_magnetos(i) );
604         break;
605         } // end FGPiston code block
606       case FGEngine::etTurbine:
607         { // FGTurbine code block
608         FGTurbine* eng = (FGTurbine*)Propulsion->GetEngine(i);
609         eng->SetAugmentation( globals->get_controls()->get_augmentation(i) );
610         eng->SetReverse( globals->get_controls()->get_reverser(i) );
611         //eng->SetInjection( globals->get_controls()->get_water_injection(i) );
612         eng->SetCutoff( globals->get_controls()->get_cutoff(i) );
613         eng->SetIgnition( globals->get_controls()->get_ignition(i) );
614         break;
615         } // end FGTurbine code block
616       case FGEngine::etRocket:
617         { // FGRocket code block
618         FGRocket* eng = (FGRocket*)Propulsion->GetEngine(i);
619         break;
620         } // end FGRocket code block
621       case FGEngine::etTurboprop:
622         { // FGTurboProp code block
623         FGTurboProp* eng = (FGTurboProp*)Propulsion->GetEngine(i);
624         eng->SetReverse( globals->get_controls()->get_reverser(i) );
625         eng->SetCutoff( globals->get_controls()->get_cutoff(i) );
626         eng->SetIgnition( globals->get_controls()->get_ignition(i) );
627
628         eng->SetGeneratorPower( globals->get_controls()->get_generator_breaker(i) );
629         eng->SetCondition( globals->get_controls()->get_condition(i) );
630         break;
631         } // end FGTurboProp code block
632       default:
633         break;
634       }
635
636       { // FGEngine code block
637       FGEngine* eng = Propulsion->GetEngine(i);
638
639       eng->SetStarter( globals->get_controls()->get_starter(i) );
640       eng->SetRunning( node->getBoolValue("running") );
641       } // end FGEngine code block
642     }
643
644
645     Propagate->SetSeaLevelRadius( get_Sea_level_radius() );
646
647     Atmosphere->SetExTemperature(
648                   9.0/5.0*(temperature->getDoubleValue()+273.15) );
649     Atmosphere->SetExPressure(pressure->getDoubleValue()*70.726566);
650     Atmosphere->SetExDensity(density->getDoubleValue());
651
652     tmp = turbulence_gain->getDoubleValue();
653     //Atmosphere->SetTurbGain(tmp * tmp * 100.0);
654
655     tmp = turbulence_rate->getDoubleValue();
656     //Atmosphere->SetTurbRate(tmp);
657
658     Atmosphere->SetWindNED( -wind_from_north->getDoubleValue(),
659                             -wind_from_east->getDoubleValue(),
660                             -wind_from_down->getDoubleValue() );
661 //    SG_LOG(SG_FLIGHT,SG_INFO, "Wind NED: "
662 //                  << get_V_north_airmass() << ", "
663 //                  << get_V_east_airmass()  << ", "
664 //                  << get_V_down_airmass() );
665
666     for (i = 0; i < Propulsion->GetNumTanks(); i++) {
667       SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
668       FGTank * tank = Propulsion->GetTank(i);
669       tank->SetContents(node->getDoubleValue("level-gal_us") * 6.6);
670 //       tank->SetContents(node->getDoubleValue("level-lbs"));
671     }
672
673     Propulsion->SetFuelFreeze((fgGetNode("/sim/freeze/fuel",true))->getBoolValue());
674     fdmex->SetChild(slaved->getBoolValue());
675
676     return true;
677 }
678
679 /******************************************************************************/
680
681 // Convert from the JSBsim generic_ struct to the FGInterface struct
682
683 bool FGJSBsim::copy_from_JSBsim()
684 {
685     unsigned int i, j;
686 /*
687     _set_Inertias( MassBalance->GetMass(),
688                    MassBalance->GetIxx(),
689                    MassBalance->GetIyy(),
690                    MassBalance->GetIzz(),
691                    MassBalance->GetIxz() );
692 */
693     _set_CG_Position( MassBalance->GetXYZcg(1),
694                       MassBalance->GetXYZcg(2),
695                       MassBalance->GetXYZcg(3) );
696
697     _set_Accels_Body( Aircraft->GetBodyAccel(1),
698                       Aircraft->GetBodyAccel(2),
699                       Aircraft->GetBodyAccel(3) );
700
701     _set_Accels_CG_Body_N ( Aircraft->GetNcg(1),
702                             Aircraft->GetNcg(2),
703                             Aircraft->GetNcg(3) );
704
705     _set_Accels_Pilot_Body( Auxiliary->GetPilotAccel(1),
706                             Auxiliary->GetPilotAccel(2),
707                             Auxiliary->GetPilotAccel(3) );
708
709     _set_Nlf( Aircraft->GetNlf() );
710
711     // Velocities
712
713     _set_Velocities_Local( Propagate->GetVel(FGJSBBase::eNorth),
714                            Propagate->GetVel(FGJSBBase::eEast),
715                            Propagate->GetVel(FGJSBBase::eDown) );
716
717     _set_Velocities_Wind_Body( Propagate->GetUVW(1),
718                                Propagate->GetUVW(2),
719                                Propagate->GetUVW(3) );
720
721     // Make the HUD work ...
722     _set_Velocities_Ground( Propagate->GetVel(FGJSBBase::eNorth),
723                             Propagate->GetVel(FGJSBBase::eEast),
724                             -Propagate->GetVel(FGJSBBase::eDown) );
725
726     _set_V_rel_wind( Auxiliary->GetVt() );
727
728     _set_V_equiv_kts( Auxiliary->GetVequivalentKTS() );
729
730     _set_V_calibrated_kts( Auxiliary->GetVcalibratedKTS() );
731
732     _set_V_ground_speed( Auxiliary->GetVground() );
733
734     _set_Omega_Body( Propagate->GetPQR(FGJSBBase::eP),
735                      Propagate->GetPQR(FGJSBBase::eQ),
736                      Propagate->GetPQR(FGJSBBase::eR) );
737
738     _set_Euler_Rates( Auxiliary->GetEulerRates(FGJSBBase::ePhi),
739                       Auxiliary->GetEulerRates(FGJSBBase::eTht),
740                       Auxiliary->GetEulerRates(FGJSBBase::ePsi) );
741
742     _set_Mach_number( Auxiliary->GetMach() );
743
744     // Positions of Visual Reference Point
745     FGLocation l = Auxiliary->GetLocationVRP();
746     _updateGeocentricPosition( l.GetLatitude(), l.GetLongitude(),
747                                l.GetRadius() - get_Sea_level_radius() );
748
749     _set_Altitude_AGL( Propagate->GetDistanceAGL() );
750     {
751       double loc_cart[3] = { l(FGJSBBase::eX), l(FGJSBBase::eY), l(FGJSBBase::eZ) };
752       double contact[3], d[3], sd, t;
753       is_valid_m(&t, d, &sd);
754       get_agl_ft(t, loc_cart, SG_METER_TO_FEET*2, contact, d, d, d, &sd);
755       double rwrad
756         = FGColumnVector3( contact[0], contact[1], contact[2] ).Magnitude();
757       _set_Runway_altitude( rwrad - get_Sea_level_radius() );
758     }
759
760     _set_Euler_Angles( Propagate->GetEuler(FGJSBBase::ePhi),
761                        Propagate->GetEuler(FGJSBBase::eTht),
762                        Propagate->GetEuler(FGJSBBase::ePsi) );
763
764     _set_Alpha( Auxiliary->Getalpha() );
765     _set_Beta( Auxiliary->Getbeta() );
766
767
768     _set_Gamma_vert_rad( Auxiliary->GetGamma() );
769
770     _set_Earth_position_angle( Inertial->GetEarthPositionAngle() );
771
772     _set_Climb_Rate( Propagate->Gethdot() );
773
774     const FGMatrix33& Tl2b = Propagate->GetTl2b();
775     for ( i = 1; i <= 3; i++ ) {
776         for ( j = 1; j <= 3; j++ ) {
777             _set_T_Local_to_Body( i, j, Tl2b(i,j) );
778         }
779     }
780
781     // Copy the engine values from JSBSim.
782     for ( i=0; i < Propulsion->GetNumEngines(); i++ ) {
783       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
784       SGPropertyNode * tnode = node->getChild("thruster", 0, true);
785       FGThruster * thruster = Propulsion->GetEngine(i)->GetThruster();
786
787       switch (Propulsion->GetEngine(i)->GetType()) {
788       case FGEngine::etPiston:
789         { // FGPiston code block
790         FGPiston* eng = (FGPiston*)Propulsion->GetEngine(i);
791         node->setDoubleValue("egt-degf", eng->getExhaustGasTemp_degF());
792         node->setDoubleValue("oil-temperature-degf", eng->getOilTemp_degF());
793         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
794         node->setDoubleValue("mp-osi", eng->getManifoldPressure_inHg());
795         // NOTE: mp-osi is not in ounces per square inch.
796         // This error is left for reasons of backwards compatibility with
797         // existing FlightGear sound and instrument configurations.
798         node->setDoubleValue("mp-inhg", eng->getManifoldPressure_inHg());
799         node->setDoubleValue("cht-degf", eng->getCylinderHeadTemp_degF());
800         node->setDoubleValue("rpm", eng->getRPM());
801         } // end FGPiston code block
802         break;
803       case FGEngine::etRocket:
804         { // FGRocket code block
805         FGRocket* eng = (FGRocket*)Propulsion->GetEngine(i);
806         } // end FGRocket code block
807         break;
808       case FGEngine::etTurbine:
809         { // FGTurbine code block
810         FGTurbine* eng = (FGTurbine*)Propulsion->GetEngine(i);
811         node->setDoubleValue("n1", eng->GetN1());
812         node->setDoubleValue("n2", eng->GetN2());
813         node->setDoubleValue("egt-degf", 32 + eng->GetEGT()*9/5);
814         node->setBoolValue("augmentation", eng->GetAugmentation());
815         node->setBoolValue("water-injection", eng->GetInjection());
816         node->setBoolValue("ignition", eng->GetIgnition());
817         node->setDoubleValue("nozzle-pos-norm", eng->GetNozzle());
818         node->setDoubleValue("inlet-pos-norm", eng->GetInlet());
819         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
820         node->setBoolValue("reversed", eng->GetReversed());
821         node->setBoolValue("cutoff", eng->GetCutoff());
822         node->setDoubleValue("epr", eng->GetEPR());
823         globals->get_controls()->set_reverser(i, eng->GetReversed() );
824         globals->get_controls()->set_cutoff(i, eng->GetCutoff() );
825         globals->get_controls()->set_water_injection(i, eng->GetInjection() );
826         globals->get_controls()->set_augmentation(i, eng->GetAugmentation() );
827         } // end FGTurbine code block
828         break;
829       case FGEngine::etTurboprop:
830         { // FGTurboProp code block
831         FGTurboProp* eng = (FGTurboProp*)Propulsion->GetEngine(i);
832         node->setDoubleValue("n1", eng->GetN1());
833         //node->setDoubleValue("n2", eng->GetN2());
834         node->setDoubleValue("itt_degf", 32 + eng->GetITT()*9/5);
835         node->setBoolValue("ignition", eng->GetIgnition());
836         node->setDoubleValue("nozzle-pos-norm", eng->GetNozzle());
837         node->setDoubleValue("inlet-pos-norm", eng->GetInlet());
838         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
839         node->setBoolValue("reversed", eng->GetReversed());
840         node->setBoolValue("cutoff", eng->GetCutoff());
841         node->setBoolValue("starting", eng->GetEngStarting());
842         node->setBoolValue("generator-power", eng->GetGeneratorPower());
843         node->setBoolValue("damaged", eng->GetCondition());
844         node->setBoolValue("ielu-intervent", eng->GetIeluIntervent());
845         node->setDoubleValue("oil-temperature-degf", eng->getOilTemp_degF());
846 //        node->setBoolValue("onfire", eng->GetFire());
847         globals->get_controls()->set_reverser(i, eng->GetReversed() );
848         globals->get_controls()->set_cutoff(i, eng->GetCutoff() );
849         } // end FGTurboProp code block
850         break;
851       case FGEngine::etElectric:
852         { // FGElectric code block
853         FGElectric* eng = (FGElectric*)Propulsion->GetEngine(i);
854         node->setDoubleValue("rpm", eng->getRPM());
855         } // end FGElectric code block
856         break;
857       case FGEngine::etUnknown:
858         break;
859       }
860
861       { // FGEngine code block
862       FGEngine* eng = Propulsion->GetEngine(i);
863       node->setDoubleValue("fuel-flow-gph", eng->getFuelFlow_gph());
864       node->setDoubleValue("thrust_lb", thruster->GetThrust());
865       node->setDoubleValue("fuel-flow_pph", eng->getFuelFlow_pph());
866       node->setBoolValue("running", eng->GetRunning());
867       node->setBoolValue("starter", eng->GetStarter());
868       node->setBoolValue("cranking", eng->GetCranking());
869       globals->get_controls()->set_starter(i, eng->GetStarter() );
870       } // end FGEngine code block
871
872       switch (thruster->GetType()) {
873       case FGThruster::ttNozzle:
874         { // FGNozzle code block
875         FGNozzle* noz = (FGNozzle*)thruster;
876         } // end FGNozzle code block
877         break;
878       case FGThruster::ttPropeller:
879         { // FGPropeller code block
880         FGPropeller* prop = (FGPropeller*)thruster;
881         tnode->setDoubleValue("rpm", thruster->GetRPM());
882         tnode->setDoubleValue("pitch", prop->GetPitch());
883         tnode->setDoubleValue("torque", prop->GetTorque());
884         tnode->setBoolValue("feathered", prop->GetFeather());
885         } // end FGPropeller code block
886         break;
887       case FGThruster::ttRotor:
888         { // FGRotor code block
889         FGRotor* rotor = (FGRotor*)thruster;
890         } // end FGRotor code block
891         break;
892       case FGThruster::ttDirect:
893         { // Direct code block
894         } // end Direct code block
895         break;
896       }
897
898     }
899
900     // Copy the fuel levels from JSBSim if fuel
901     // freeze not enabled.
902     if ( ! Propulsion->GetFuelFreeze() ) {
903       for (i = 0; i < Propulsion->GetNumTanks(); i++) {
904         SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
905         FGTank* tank = Propulsion->GetTank(i);
906         double contents = tank->GetContents();
907         double temp = tank->GetTemperature_degC();
908         node->setDoubleValue("level-gal_us", contents/6.6);
909         node->setDoubleValue("level-lbs", contents);
910         if (temp != -9999.0) node->setDoubleValue("temperature_degC", temp);
911       }
912     }
913
914     update_gear();
915
916     stall_warning->setDoubleValue( Aerodynamics->GetStallWarn() );
917
918     elevator_pos_pct->setDoubleValue( FCS->GetDePos(ofNorm) );
919     left_aileron_pos_pct->setDoubleValue( FCS->GetDaLPos(ofNorm) );
920     right_aileron_pos_pct->setDoubleValue( FCS->GetDaRPos(ofNorm) );
921     rudder_pos_pct->setDoubleValue( -1*FCS->GetDrPos(ofNorm) );
922     flap_pos_pct->setDoubleValue( FCS->GetDfPos(ofNorm) );
923     speedbrake_pos_pct->setDoubleValue( FCS->GetDsbPos(ofNorm) );
924     spoilers_pos_pct->setDoubleValue( FCS->GetDspPos(ofNorm) );
925     tailhook_pos_pct->setDoubleValue( FCS->GetTailhookPos() );
926     wing_fold_pos_pct->setDoubleValue( FCS->GetWingFoldPos() );
927
928     // force a sim crashed if crashed (altitude AGL < 0)
929     if (get_Altitude_AGL() < -100.0) {
930          fdmex->SuspendIntegration();
931          crashed = true;
932     }
933
934     return true;
935 }
936
937
938 bool FGJSBsim::ToggleDataLogging(void)
939 {
940   // ToDo: handle this properly
941   fdmex->DisableOutput();
942   return false;
943 }
944
945
946 bool FGJSBsim::ToggleDataLogging(bool state)
947 {
948     if (state) {
949       fdmex->EnableOutput();
950       return true;
951     } else {
952       fdmex->DisableOutput();
953       return false;
954     }
955 }
956
957
958 //Positions
959 void FGJSBsim::set_Latitude(double lat)
960 {
961     static SGConstPropertyNode_ptr altitude = fgGetNode("/position/altitude-ft");
962     double alt;
963     double sea_level_radius_meters, lat_geoc;
964
965     // In case we're not trimming
966     FGInterface::set_Latitude(lat);
967
968     if ( altitude->getDoubleValue() > -9990 ) {
969       alt = altitude->getDoubleValue();
970     } else {
971       alt = 0.0;
972     }
973
974     update_ic();
975     SG_LOG(SG_FLIGHT,SG_INFO,"FGJSBsim::set_Latitude: " << lat );
976     SG_LOG(SG_FLIGHT,SG_INFO," cur alt (ft) =  " << alt );
977
978     sgGeodToGeoc( lat, alt * SG_FEET_TO_METER,
979                       &sea_level_radius_meters, &lat_geoc );
980     _set_Sea_level_radius( sea_level_radius_meters * SG_METER_TO_FEET  );
981     fgic->SetSeaLevelRadiusFtIC( sea_level_radius_meters * SG_METER_TO_FEET  );
982     fgic->SetLatitudeRadIC( lat_geoc );
983     needTrim=true;
984 }
985
986
987 void FGJSBsim::set_Longitude(double lon)
988 {
989     SG_LOG(SG_FLIGHT,SG_INFO,"FGJSBsim::set_Longitude: " << lon );
990
991     // In case we're not trimming
992     FGInterface::set_Longitude(lon);
993
994     update_ic();
995     fgic->SetLongitudeRadIC( lon );
996     needTrim=true;
997 }
998
999 // Sets the altitude above sea level.
1000 void FGJSBsim::set_Altitude(double alt)
1001 {
1002     static SGConstPropertyNode_ptr latitude = fgGetNode("/position/latitude-deg");
1003
1004     double sea_level_radius_meters,lat_geoc;
1005
1006     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Altitude: " << alt );
1007     SG_LOG(SG_FLIGHT,SG_INFO, "  lat (deg) = " << latitude->getDoubleValue() );
1008
1009     // In case we're not trimming
1010     FGInterface::set_Altitude(alt);
1011
1012     update_ic();
1013     sgGeodToGeoc( latitude->getDoubleValue() * SGD_DEGREES_TO_RADIANS, alt,
1014                   &sea_level_radius_meters, &lat_geoc);
1015     _set_Sea_level_radius( sea_level_radius_meters * SG_METER_TO_FEET  );
1016     fgic->SetSeaLevelRadiusFtIC( sea_level_radius_meters * SG_METER_TO_FEET );
1017     SG_LOG(SG_FLIGHT, SG_INFO,
1018           "Terrain elevation: " << FGInterface::get_Runway_altitude() * SG_METER_TO_FEET );
1019     fgic->SetLatitudeRadIC( lat_geoc );
1020     fgic->SetAltitudeASLFtIC(alt);
1021     needTrim=true;
1022 }
1023
1024 void FGJSBsim::set_V_calibrated_kts(double vc)
1025 {
1026     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_V_calibrated_kts: " <<  vc );
1027
1028     // In case we're not trimming
1029     FGInterface::set_V_calibrated_kts(vc);
1030
1031     update_ic();
1032     fgic->SetVcalibratedKtsIC(vc);
1033     needTrim=true;
1034 }
1035
1036 void FGJSBsim::set_Mach_number(double mach)
1037 {
1038     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Mach_number: " <<  mach );
1039
1040     // In case we're not trimming
1041     FGInterface::set_Mach_number(mach);
1042
1043     update_ic();
1044     fgic->SetMachIC(mach);
1045     needTrim=true;
1046 }
1047
1048 void FGJSBsim::set_Velocities_Local( double north, double east, double down )
1049 {
1050     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Velocities_Local: "
1051        << north << ", " <<  east << ", " << down );
1052
1053     // In case we're not trimming
1054     FGInterface::set_Velocities_Local(north, east, down);
1055
1056     update_ic();
1057     fgic->SetVNorthFpsIC(north);
1058     fgic->SetVEastFpsIC(east);
1059     fgic->SetVDownFpsIC(down);
1060     needTrim=true;
1061 }
1062
1063 void FGJSBsim::set_Velocities_Wind_Body( double u, double v, double w)
1064 {
1065     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Velocities_Wind_Body: "
1066        << u << ", " <<  v << ", " <<  w );
1067
1068     // In case we're not trimming
1069     FGInterface::set_Velocities_Wind_Body(u, v, w);
1070
1071     update_ic();
1072     fgic->SetUBodyFpsIC(u);
1073     fgic->SetVBodyFpsIC(v);
1074     fgic->SetWBodyFpsIC(w);
1075     needTrim=true;
1076 }
1077
1078 //Euler angles
1079 void FGJSBsim::set_Euler_Angles( double phi, double theta, double psi )
1080 {
1081     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Euler_Angles: "
1082        << phi << ", " << theta << ", " << psi );
1083
1084     // In case we're not trimming
1085     FGInterface::set_Euler_Angles(phi, theta, psi);
1086
1087     update_ic();
1088     fgic->SetThetaRadIC(theta);
1089     fgic->SetPhiRadIC(phi);
1090     fgic->SetPsiRadIC(psi);
1091     needTrim=true;
1092 }
1093
1094 //Flight Path
1095 void FGJSBsim::set_Climb_Rate( double roc)
1096 {
1097     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Climb_Rate: " << roc );
1098
1099     // In case we're not trimming
1100     FGInterface::set_Climb_Rate(roc);
1101
1102     update_ic();
1103     //since both climb rate and flight path angle are set in the FG
1104     //startup sequence, something is needed to keep one from cancelling
1105     //out the other.
1106     if( !(fabs(roc) > 1 && fabs(fgic->GetFlightPathAngleRadIC()) < 0.01) ) {
1107       fgic->SetClimbRateFpsIC(roc);
1108     }
1109     needTrim=true;
1110 }
1111
1112 void FGJSBsim::set_Gamma_vert_rad( double gamma)
1113 {
1114     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Gamma_vert_rad: " << gamma );
1115
1116     update_ic();
1117     if( !(fabs(gamma) < 0.01 && fabs(fgic->GetClimbRateFpsIC()) > 1) ) {
1118       fgic->SetFlightPathAngleRadIC(gamma);
1119     }
1120     needTrim=true;
1121 }
1122
1123 void FGJSBsim::init_gear(void )
1124 {
1125     FGGroundReactions* gr=fdmex->GetGroundReactions();
1126     int Ngear=GroundReactions->GetNumGearUnits();
1127     for (int i=0;i<Ngear;i++) {
1128       FGLGear *gear = gr->GetGearUnit(i);
1129       SGPropertyNode * node = fgGetNode("gear/gear", i, true);
1130       node->setDoubleValue("xoffset-in", gear->GetBodyLocation()(1));
1131       node->setDoubleValue("yoffset-in", gear->GetBodyLocation()(2));
1132       node->setDoubleValue("zoffset-in", gear->GetBodyLocation()(3));
1133       node->setBoolValue("wow", gear->GetWOW());
1134       node->setDoubleValue("rollspeed-ms", gear->GetWheelRollVel()*0.3043);
1135       node->setBoolValue("has-brake", gear->GetBrakeGroup() > 0);
1136       node->setDoubleValue("position-norm", gear->GetGearUnitPos());
1137       node->setDoubleValue("tire-pressure-norm", gear->GetTirePressure());
1138       node->setDoubleValue("compression-norm", gear->GetCompLen());
1139       node->setDoubleValue("compression-ft", gear->GetCompLen());
1140       if ( gear->GetSteerable() )
1141         node->setDoubleValue("steering-norm", gear->GetSteerNorm());
1142     }
1143 }
1144
1145 void FGJSBsim::update_gear(void)
1146 {
1147     FGGroundReactions* gr=fdmex->GetGroundReactions();
1148     int Ngear=GroundReactions->GetNumGearUnits();
1149     for (int i=0;i<Ngear;i++) {
1150       FGLGear *gear = gr->GetGearUnit(i);
1151       SGPropertyNode * node = fgGetNode("gear/gear", i, true);
1152       node->getChild("wow", 0, true)->setBoolValue( gear->GetWOW());
1153       node->getChild("rollspeed-ms", 0, true)->setDoubleValue(gear->GetWheelRollVel()*0.3043);
1154       node->getChild("position-norm", 0, true)->setDoubleValue(gear->GetGearUnitPos());
1155       gear->SetTirePressure(node->getDoubleValue("tire-pressure-norm"));
1156       node->setDoubleValue("compression-norm", gear->GetCompLen());
1157       node->setDoubleValue("compression-ft", gear->GetCompLen());
1158       if ( gear->GetSteerable() )
1159         node->setDoubleValue("steering-norm", gear->GetSteerNorm());
1160     }
1161 }
1162
1163 void FGJSBsim::do_trim(void)
1164 {
1165   FGTrim *fgtrim;
1166
1167   if ( fgGetBool("/sim/presets/onground") )
1168   {
1169     fgtrim = new FGTrim(fdmex,tGround);
1170   } else {
1171     fgtrim = new FGTrim(fdmex,tLongitudinal);
1172   }
1173
1174   if ( !fgtrim->DoTrim() ) {
1175     fgtrim->Report();
1176     fgtrim->TrimStats();
1177   } else {
1178     trimmed->setBoolValue(true);
1179   }
1180   delete fgtrim;
1181
1182   pitch_trim->setDoubleValue( FCS->GetPitchTrimCmd() );
1183   throttle_trim->setDoubleValue( FCS->GetThrottleCmd(0) );
1184   aileron_trim->setDoubleValue( FCS->GetDaCmd() );
1185   rudder_trim->setDoubleValue( FCS->GetDrCmd() );
1186
1187   globals->get_controls()->set_elevator_trim(FCS->GetPitchTrimCmd());
1188   globals->get_controls()->set_elevator(FCS->GetDeCmd());
1189   globals->get_controls()->set_throttle(FGControls::ALL_ENGINES,
1190   FCS->GetThrottleCmd(0));
1191
1192   globals->get_controls()->set_aileron(FCS->GetDaCmd());
1193   globals->get_controls()->set_rudder( FCS->GetDrCmd());
1194
1195   SG_LOG( SG_FLIGHT, SG_INFO, "  Trim complete" );
1196 }
1197
1198 void FGJSBsim::update_ic(void)
1199 {
1200    if ( !needTrim ) {
1201      fgic->SetLatitudeRadIC(get_Lat_geocentric() );
1202      fgic->SetLongitudeRadIC( get_Longitude() );
1203      fgic->SetAltitudeASLFtIC( get_Altitude() );
1204      fgic->SetVcalibratedKtsIC( get_V_calibrated_kts() );
1205      fgic->SetThetaRadIC( get_Theta() );
1206      fgic->SetPhiRadIC( get_Phi() );
1207      fgic->SetPsiRadIC( get_Psi() );
1208      fgic->SetClimbRateFpsIC( get_Climb_Rate() );
1209    }
1210 }
1211
1212 bool
1213 FGJSBsim::get_agl_ft(double t, const double pt[3], double alt_off,
1214                      double contact[3], double normal[3], double vel[3],
1215                      double angularVel[3], double *agl)
1216 {
1217    const SGMaterial* material;
1218    simgear::BVHNode::Id id;
1219    if (!FGInterface::get_agl_ft(t, pt, alt_off, contact, normal, vel,
1220                                 angularVel, material, id))
1221        return false;
1222    SGGeod geodPt = SGGeod::fromCart(SG_FEET_TO_METER*SGVec3d(pt));
1223    SGQuatd hlToEc = SGQuatd::fromLonLat(geodPt);
1224    *agl = dot(hlToEc.rotate(SGVec3d(0, 0, 1)), SGVec3d(contact) - SGVec3d(pt));
1225    return true;
1226 }
1227
1228 inline static double dot3(const FGColumnVector3& a, const FGColumnVector3& b)
1229 {
1230     return a(1) * b(1) + a(2) * b(2) + a(3) * b(3);
1231 }
1232
1233 inline static double sqr(double x)
1234 {
1235     return x * x;
1236 }
1237
1238 static double angle_diff(double a, double b)
1239 {
1240     double diff = fabs(a - b);
1241     if (diff > 180) diff = 360 - diff;
1242     
1243     return diff;
1244 }
1245
1246 static void check_hook_solution(const FGColumnVector3& ground_normal_body, double E, double hook_length, double sin_fi_guess, double cos_fi_guess, double* sin_fis, double* cos_fis, double* fis, int* points)
1247 {
1248     FGColumnVector3 tip(-hook_length * cos_fi_guess, 0, hook_length * sin_fi_guess);
1249     double dist = dot3(tip, ground_normal_body);
1250     if (fabs(dist + E) < 0.0001) {
1251         sin_fis[*points] = sin_fi_guess;
1252         cos_fis[*points] = cos_fi_guess;
1253         fis[*points] = atan2(sin_fi_guess, cos_fi_guess) * SG_RADIANS_TO_DEGREES;
1254         (*points)++;
1255     } 
1256 }
1257
1258
1259 static void check_hook_solution(const FGColumnVector3& ground_normal_body, double E, double hook_length, double sin_fi_guess, double* sin_fis, double* cos_fis, double* fis, int* points)
1260 {
1261     if (sin_fi_guess >= -1 && sin_fi_guess <= 1) {
1262         double cos_fi_guess = sqrt(1 - sqr(sin_fi_guess));
1263         check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess, cos_fi_guess, sin_fis, cos_fis, fis, points);
1264         if (fabs(cos_fi_guess) > SG_EPSILON) {
1265             check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess, -cos_fi_guess, sin_fis, cos_fis, fis, points);
1266         }
1267     }
1268 }
1269
1270 void FGJSBsim::update_external_forces(double t_off)
1271 {
1272     const FGMatrix33& Tb2l = Propagate->GetTb2l();
1273     const FGMatrix33& Tl2b = Propagate->GetTl2b();
1274     const FGLocation& Location = Propagate->GetLocation();
1275     const FGMatrix33& Tec2l = Location.GetTec2l();
1276         
1277     double hook_area[4][3];
1278     
1279     FGColumnVector3 hook_root_body = MassBalance->StructuralToBody(hook_root_struct);
1280     FGColumnVector3 hook_root = Location.LocalToLocation(Tb2l *   hook_root_body);
1281     hook_area[1][0] = hook_root(1);
1282     hook_area[1][1] = hook_root(2);
1283     hook_area[1][2] = hook_root(3);
1284     
1285     hook_length = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-length-ft", 6.75);
1286     double fi_min = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-min-deg", -18);
1287     double fi_max = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-max-deg", 30);
1288     double fi = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-norm") * (fi_max - fi_min) + fi_min;
1289     double cos_fi = cos(fi * SG_DEGREES_TO_RADIANS);
1290     double sin_fi = sin(fi * SG_DEGREES_TO_RADIANS);
1291
1292     FGColumnVector3 hook_tip_body = hook_root_body;
1293     hook_tip_body(1) -= hook_length * cos_fi;
1294     hook_tip_body(3) += hook_length * sin_fi;    
1295     
1296     double contact[3];
1297     double ground_normal[3];
1298     double ground_vel[3];
1299     double ground_angular_vel[3];
1300     double root_agl_ft;
1301
1302     if (!got_wire) {
1303         bool got = get_agl_ft(t_off, hook_area[1], 0, contact, ground_normal,
1304                               ground_vel, ground_angular_vel, &root_agl_ft);
1305         if (got && root_agl_ft > 0 && root_agl_ft < hook_length) {
1306             FGColumnVector3 ground_normal_body = Tl2b * (Tec2l * FGColumnVector3(ground_normal[0], ground_normal[1], ground_normal[2]));
1307             FGColumnVector3 contact_body = Tl2b * Location.LocationToLocal(FGColumnVector3(contact[0], contact[1], contact[2]));
1308             double D = -dot3(contact_body, ground_normal_body);
1309
1310             // check hook tip agl against same ground plane
1311             double hook_tip_agl_ft = dot3(hook_tip_body, ground_normal_body) + D;
1312             if (hook_tip_agl_ft < 0) {
1313
1314                 // hook tip: hx - l cos, hy, hz + l sin
1315                 // on ground:  - n0 l cos + n2 l sin + E = 0
1316
1317                 double E = D + dot3(hook_root_body, ground_normal_body);
1318
1319                 // substitue x = sin fi, cos fi = sqrt(1 - x * x)
1320                 // and rearrange to get a quadratic with coeffs:
1321                 double a = sqr(hook_length) * (sqr(ground_normal_body(1)) + sqr(ground_normal_body(3)));
1322                 double b = 2 * E * ground_normal_body(3) * hook_length;
1323                 double c = sqr(E) - sqr(ground_normal_body(1) * hook_length);   
1324
1325                 double disc = sqr(b) - 4 * a * c;
1326                 if (disc >= 0) {
1327                     double delta = sqrt(disc) / (2 * a);
1328                 
1329                     // allow 4 solutions for safety, should never happen
1330                     double sin_fis[4];
1331                     double cos_fis[4];
1332                     double fis[4];
1333                     int points = 0;
1334                 
1335                     double sin_fi_guess = -b / (2 * a) - delta;
1336                     check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess, sin_fis, cos_fis, fis, &points);
1337                     check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess + 2 * delta, sin_fis, cos_fis, fis, &points);
1338                 
1339                     if (points == 2) {
1340                         double diff1 = angle_diff(fi, fis[0]);
1341                         double diff2 = angle_diff(fi, fis[1]);
1342                         int point = diff1 < diff2 ? 0 : 1;
1343                         fi = fis[point];
1344                         sin_fi = sin_fis[point];
1345                         cos_fi = cos_fis[point];
1346                         hook_tip_body(1) = hook_root_body(1) - hook_length * cos_fi;
1347                         hook_tip_body(3) = hook_root_body(3) + hook_length * sin_fi;
1348                     }
1349                 }
1350             }
1351         }
1352     } else {
1353         FGColumnVector3 hook_root_vel = Propagate->GetVel() + (Tb2l * (Propagate->GetPQR() *  hook_root_body));
1354         double wire_ends_ec[2][3];
1355         double wire_vel_ec[2][3];
1356         get_wire_ends_ft(t_off, wire_ends_ec, wire_vel_ec);
1357         FGColumnVector3 wire_vel_1 = Tec2l * FGColumnVector3(wire_vel_ec[0][0], wire_vel_ec[0][1], wire_vel_ec[0][2]);
1358         FGColumnVector3 wire_vel_2 = Tec2l * FGColumnVector3(wire_vel_ec[1][0], wire_vel_ec[1][1], wire_vel_ec[1][2]);
1359         FGColumnVector3 rel_vel = hook_root_vel - (wire_vel_1 + wire_vel_2) / 2;
1360         if (rel_vel.Magnitude() < 3) {
1361             got_wire = false;
1362             release_wire();
1363             fgSetDouble("/fdm/jsbsim/external_reactions/hook/magnitude", 0.0);
1364         } else {
1365             FGColumnVector3 wire_end1_body = Tl2b * Location.LocationToLocal(FGColumnVector3(wire_ends_ec[0][0], wire_ends_ec[0][1], wire_ends_ec[0][2])) - hook_root_body;
1366             FGColumnVector3 wire_end2_body = Tl2b * Location.LocationToLocal(FGColumnVector3(wire_ends_ec[1][0], wire_ends_ec[1][1], wire_ends_ec[1][2])) - hook_root_body;
1367             FGColumnVector3 force_plane_normal = wire_end1_body * wire_end2_body;
1368             force_plane_normal.Normalize();
1369             cos_fi = dot3(force_plane_normal, FGColumnVector3(0, 0, 1));
1370             if (cos_fi < 0) cos_fi = -cos_fi;
1371             sin_fi = sqrt(1 - sqr(cos_fi));
1372             fi = atan2(sin_fi, cos_fi) * SG_RADIANS_TO_DEGREES;
1373         
1374             fgSetDouble("/fdm/jsbsim/external_reactions/hook/x", -cos_fi);
1375             fgSetDouble("/fdm/jsbsim/external_reactions/hook/y", 0);
1376             fgSetDouble("/fdm/jsbsim/external_reactions/hook/z", sin_fi);
1377             fgSetDouble("/fdm/jsbsim/external_reactions/hook/magnitude", fgGetDouble("/fdm/jsbsim/systems/hook/force"));
1378         }
1379     }
1380
1381     FGColumnVector3 hook_tip = Location.LocalToLocation(Tb2l * hook_tip_body);
1382
1383     hook_area[0][0] = hook_tip(1);
1384     hook_area[0][1] = hook_tip(2);
1385     hook_area[0][2] = hook_tip(3);
1386
1387     if (!got_wire) {
1388         // The previous positions.
1389         hook_area[2][0] = last_hook_root[0];
1390         hook_area[2][1] = last_hook_root[1];
1391         hook_area[2][2] = last_hook_root[2];
1392         hook_area[3][0] = last_hook_tip[0];
1393         hook_area[3][1] = last_hook_tip[1];
1394         hook_area[3][2] = last_hook_tip[2];
1395
1396         // Check if we caught a wire.
1397         // Returns true if we caught one.
1398         if (caught_wire_ft(t_off, hook_area)) {
1399                 got_wire = true;
1400         }
1401     }
1402     
1403     // save actual position as old position ...
1404     last_hook_tip[0] = hook_area[0][0];
1405     last_hook_tip[1] = hook_area[0][1];
1406     last_hook_tip[2] = hook_area[0][2];
1407     last_hook_root[0] = hook_area[1][0];
1408     last_hook_root[1] = hook_area[1][1];
1409     last_hook_root[2] = hook_area[1][2];
1410     
1411     fgSetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-deg", fi);
1412 }
1413