src/FDM/JSBSim/JSBSim.cxx

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