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 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 #include <simgear/sg_inlines.h>
  30
  31 #include <stdio.h>    //    size_t
  32 #include <string>
  33
  34 #include <simgear/constants.h>
  35 #include <simgear/debug/logstream.hxx>
  36 #include <simgear/math/sg_geodesy.hxx>
  37 #include <simgear/misc/sg_path.hxx>
  38 #include <simgear/structure/commands.hxx>
  39
  40 #include <FDM/flight.hxx>
  41
  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/initialization/FGInitialCondition.h>
  50 #include <FDM/JSBSim/initialization/FGTrim.h>
  51 #include <FDM/JSBSim/models/FGModel.h>
  52 #include <FDM/JSBSim/models/FGAircraft.h>
  53 #include <FDM/JSBSim/models/FGFCS.h>
  54 #include <FDM/JSBSim/models/FGPropagate.h>
  55 #include <FDM/JSBSim/models/FGAuxiliary.h>
  56 #include <FDM/JSBSim/models/FGInertial.h>
  57 #include <FDM/JSBSim/models/FGAtmosphere.h>
  58 #include <FDM/JSBSim/models/FGMassBalance.h>
  59 #include <FDM/JSBSim/models/FGAerodynamics.h>
  60 #include <FDM/JSBSim/models/FGLGear.h>
  61 #include <FDM/JSBSim/models/FGGroundReactions.h>
  62 #include <FDM/JSBSim/models/FGPropulsion.h>
  63 #include <FDM/JSBSim/models/propulsion/FGEngine.h>
  64 #include <FDM/JSBSim/models/propulsion/FGPiston.h>
  65 #include <FDM/JSBSim/models/propulsion/FGTurbine.h>
  66 #include <FDM/JSBSim/models/propulsion/FGTurboProp.h>
  67 #include <FDM/JSBSim/models/propulsion/FGRocket.h>
  68 #include <FDM/JSBSim/models/propulsion/FGElectric.h>
  69 #include <FDM/JSBSim/models/propulsion/FGNozzle.h>
  70 #include <FDM/JSBSim/models/propulsion/FGPropeller.h>
  71 #include <FDM/JSBSim/models/propulsion/FGRotor.h>
  72 #include <FDM/JSBSim/models/propulsion/FGTank.h>
  73 #include <FDM/JSBSim/input_output/FGPropertyManager.h>
  74 #include <FDM/JSBSim/input_output/FGGroundCallback.h>
  75
  76 using namespace JSBSim;
  77
  78 static inline double
  79 FMAX (double a, double b)
  80 {
  81   return a > b ? a : b;
  82 }
  83
  84 class FGFSGroundCallback : public FGGroundCallback {
  85 public:
  86   FGFSGroundCallback(FGJSBsim* ifc) : mInterface(ifc) {}
  87   virtual ~FGFSGroundCallback() {}
  88
  89   /** Get the altitude above sea level dependent on the location. */
  90   virtual double GetAltitude(const FGLocation& l) const {
  91     double pt[3] = { SG_FEET_TO_METER*l(eX),
  92                      SG_FEET_TO_METER*l(eY),
  93                      SG_FEET_TO_METER*l(eZ) };
  94     double lat, lon, alt;
  95     sgCartToGeod( pt, &lat, &lon, &alt);
  96     return alt * SG_METER_TO_FEET;
  97   }
  98
  99   /** Compute the altitude above ground. */
 100   virtual double GetAGLevel(double t, const FGLocation& l,
 101                             FGLocation& cont, FGColumnVector3& n,
 102                             FGColumnVector3& v, FGColumnVector3& w) const {
 103     double loc_cart[3] = { l(eX), l(eY), l(eZ) };
 104     double contact[3], normal[3], vel[3], angularVel[3], agl = 0;
 105     mInterface->get_agl_ft(t, loc_cart, SG_METER_TO_FEET*2, contact, normal,
 106                            vel, angularVel, &agl);
 107     n = FGColumnVector3( normal[0], normal[1], normal[2] );
 108     v = FGColumnVector3( vel[0], vel[1], vel[2] );
 109     w = FGColumnVector3( angularVel[0], angularVel[1], angularVel[2] );
 110     cont = FGColumnVector3( contact[0], contact[1], contact[2] );
 111     return agl;
 112   }
 113 private:
 114   FGJSBsim* mInterface;
 115 };
 116
 117 /******************************************************************************/
 118
 119 FGJSBsim::FGJSBsim( double dt )
 120   : FGInterface(dt), got_wire(false)
 121 {
 122     bool result;
 123                                 // Set up the debugging level
 124                                 // FIXME: this will not respond to
 125                                 // runtime changes
 126
 127                                 // if flight is excluded, don't bother
 128     if ((logbuf::get_log_classes() & SG_FLIGHT) != 0) {
 129
 130                                 // do a rough-and-ready mapping to
 131                                 // the levels documented in FGFDMExec.h
 132         switch (logbuf::get_log_priority()) {
 133         case SG_BULK:
 134             FGJSBBase::debug_lvl = 0x1f;
 135             break;
 136         case SG_DEBUG:
 137             FGJSBBase::debug_lvl = 0x0f;
 138         case SG_INFO:
 139             FGJSBBase::debug_lvl = 0x01;
 140             break;
 141         case SG_WARN:
 142         case SG_ALERT:
 143             FGJSBBase::debug_lvl = 0x00;
 144             break;
 145         }
 146     }
 147
 148     fdmex = new FGFDMExec( (FGPropertyManager*)globals->get_props() );
 149
 150     // Register ground callback.
 151     fdmex->SetGroundCallback( new FGFSGroundCallback(this) );
 152
 153     Atmosphere      = fdmex->GetAtmosphere();
 154     FCS             = fdmex->GetFCS();
 155     MassBalance     = fdmex->GetMassBalance();
 156     Propulsion      = fdmex->GetPropulsion();
 157     Aircraft        = fdmex->GetAircraft();
 158     Propagate        = fdmex->GetPropagate();
 159     Auxiliary       = fdmex->GetAuxiliary();
 160     Inertial        = fdmex->GetInertial();
 161     Aerodynamics    = fdmex->GetAerodynamics();
 162     GroundReactions = fdmex->GetGroundReactions();
 163
 164     fgic=fdmex->GetIC();
 165     needTrim=true;
 166
 167     SGPath aircraft_path( fgGetString("/sim/aircraft-dir") );
 168
 169     SGPath engine_path( fgGetString("/sim/aircraft-dir") );
 170     engine_path.append( "Engine" );
 171
 172     SGPath systems_path( fgGetString("/sim/aircraft-dir") );
 173     systems_path.append( "Systems" );
 174
 175 // deprecate sim-time-sec for simulation/sim-time-sec
 176 // remove alias with increased configuration file version number (2.1 or later)
 177     SGPropertyNode * node = fgGetNode("/fdm/jsbsim/simulation/sim-time-sec");
 178     fgGetNode("/fdm/jsbsim/sim-time-sec", true)->alias( node );
 179 // end of sim-time-sec deprecation patch
 180
 181     fdmex->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       double d;
 217       SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
 218       FGTank* tank = Propulsion->GetTank(i);
 219
 220       d = node->getNode( "density-ppg", true )->getDoubleValue();
 221       if( d > 0.0 ) {
 222         tank->SetDensity( d );
 223       } else {
 224         node->getNode( "density-ppg", true )->setDoubleValue( SG_MAX2<double>(tank->GetDensity(), 0.1) );
 225       }
 226
 227       d = node->getNode( "level-lbs", true )->getDoubleValue();
 228       if( d > 0.0 ) {
 229         tank->SetContents( d );
 230       } else {
 231         node->getNode( "level-lbs", true )->setDoubleValue( tank->GetContents() );
 232       }
 233       /* Capacity is read-only in FGTank and can't be overwritten from FlightGear */
 234       node->getNode("capacity-gal_us", true )->setDoubleValue( tank->GetCapacityGallons() );
 235     }
 236     Propulsion->SetFuelFreeze((fgGetNode("/sim/freeze/fuel",true))->getBoolValue());
 237
 238     fgSetDouble("/fdm/trim/pitch-trim", FCS->GetPitchTrimCmd());
 239     fgSetDouble("/fdm/trim/throttle",   FCS->GetThrottleCmd(0));
 240     fgSetDouble("/fdm/trim/aileron",    FCS->GetDaCmd());
 241     fgSetDouble("/fdm/trim/rudder",     FCS->GetDrCmd());
 242
 243     startup_trim = fgGetNode("/sim/presets/trim", true);
 244
 245     trimmed = fgGetNode("/fdm/trim/trimmed", true);
 246     trimmed->setBoolValue(false);
 247
 248     pitch_trim = fgGetNode("/fdm/trim/pitch-trim", true );
 249     throttle_trim = fgGetNode("/fdm/trim/throttle", true );
 250     aileron_trim = fgGetNode("/fdm/trim/aileron", true );
 251     rudder_trim = fgGetNode("/fdm/trim/rudder", true );
 252
 253     stall_warning = fgGetNode("/sim/alarms/stall-warning",true);
 254     stall_warning->setDoubleValue(0);
 255
 256
 257     flap_pos_pct=fgGetNode("/surface-positions/flap-pos-norm",true);
 258     elevator_pos_pct=fgGetNode("/surface-positions/elevator-pos-norm",true);
 259     left_aileron_pos_pct
 260         =fgGetNode("/surface-positions/left-aileron-pos-norm",true);
 261     right_aileron_pos_pct
 262         =fgGetNode("/surface-positions/right-aileron-pos-norm",true);
 263     rudder_pos_pct=fgGetNode("/surface-positions/rudder-pos-norm",true);
 264     speedbrake_pos_pct
 265         =fgGetNode("/surface-positions/speedbrake-pos-norm",true);
 266     spoilers_pos_pct=fgGetNode("/surface-positions/spoilers-pos-norm",true);
 267     tailhook_pos_pct=fgGetNode("/gear/tailhook/position-norm",true);
 268     wing_fold_pos_pct=fgGetNode("surface-positions/wing-fold-pos-norm",true);
 269
 270     elevator_pos_pct->setDoubleValue(0);
 271     left_aileron_pos_pct->setDoubleValue(0);
 272     right_aileron_pos_pct->setDoubleValue(0);
 273     rudder_pos_pct->setDoubleValue(0);
 274     flap_pos_pct->setDoubleValue(0);
 275     speedbrake_pos_pct->setDoubleValue(0);
 276     spoilers_pos_pct->setDoubleValue(0);
 277
 278     ab_brake_engaged = fgGetNode("/autopilot/autobrake/engaged", true);
 279     ab_brake_left_pct = fgGetNode("/autopilot/autobrake/brake-left-output", true);
 280     ab_brake_right_pct = fgGetNode("/autopilot/autobrake/brake-right-output", true);
 281
 282     temperature = fgGetNode("/environment/temperature-degc",true);
 283     pressure = fgGetNode("/environment/pressure-inhg",true);
 284     density = fgGetNode("/environment/density-slugft3",true);
 285     turbulence_gain = fgGetNode("/environment/turbulence/magnitude-norm",true);
 286     turbulence_rate = fgGetNode("/environment/turbulence/rate-hz",true);
 287
 288     wind_from_north= fgGetNode("/environment/wind-from-north-fps",true);
 289     wind_from_east = fgGetNode("/environment/wind-from-east-fps" ,true);
 290     wind_from_down = fgGetNode("/environment/wind-from-down-fps" ,true);
 291
 292     slaved = fgGetNode("/sim/slaved/enabled", true);
 293
 294     for (unsigned int i = 0; i < Propulsion->GetNumEngines(); i++) {
 295       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 296       Propulsion->GetEngine(i)->GetThruster()->SetRPM(node->getDoubleValue("rpm") /
 297                      Propulsion->GetEngine(i)->GetThruster()->GetGearRatio());
 298     }
 299
 300     hook_root_struct = FGColumnVector3(
 301         fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-offset-x-in", 196),
 302         fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-offset-y-in", 0),
 303         fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-offset-z-in", -16));
 304     last_hook_tip[0] = 0; last_hook_tip[1] = 0; last_hook_tip[2] = 0;
 305     last_hook_root[0] = 0; last_hook_root[1] = 0; last_hook_root[2] = 0;
 306
 307     crashed = false;
 308 }
 309
 310 /******************************************************************************/
 311 FGJSBsim::~FGJSBsim(void)
 312 {
 313   delete fdmex;
 314 }
 315
 316 /******************************************************************************/
 317
 318 // Initialize the JSBsim flight model, dt is the time increment for
 319 // each subsequent iteration through the EOM
 320
 321 void FGJSBsim::init()
 322 {
 323     SG_LOG( SG_FLIGHT, SG_INFO, "Starting and initializing JSBsim" );
 324
 325     // Explicitly call the superclass's
 326     // init method first.
 327
 328     if (fgGetBool("/environment/params/control-fdm-atmosphere")) {
 329       Atmosphere->UseExternal();
 330       Atmosphere->SetExTemperature(
 331                   9.0/5.0*(temperature->getDoubleValue()+273.15) );
 332       Atmosphere->SetExPressure(pressure->getDoubleValue()*70.726566);
 333       Atmosphere->SetExDensity(density->getDoubleValue());
 334       Atmosphere->SetTurbType(FGAtmosphere::ttCulp);
 335       Atmosphere->SetTurbGain(turbulence_gain->getDoubleValue());
 336       Atmosphere->SetTurbRate(turbulence_rate->getDoubleValue());
 337
 338     } else {
 339       Atmosphere->UseInternal();
 340     }
 341
 342     fgic->SetVNorthFpsIC( -wind_from_north->getDoubleValue() );
 343     fgic->SetVEastFpsIC( -wind_from_east->getDoubleValue() );
 344     fgic->SetVDownFpsIC( -wind_from_down->getDoubleValue() );
 345
 346     //Atmosphere->SetExTemperature(get_Static_temperature());
 347     //Atmosphere->SetExPressure(get_Static_pressure());
 348     //Atmosphere->SetExDensity(get_Density());
 349     SG_LOG(SG_FLIGHT,SG_INFO,"T,p,rho: " << fdmex->GetAtmosphere()->GetTemperature()
 350      << ", " << fdmex->GetAtmosphere()->GetPressure()
 351      << ", " << fdmex->GetAtmosphere()->GetDensity() );
 352
 353 // deprecate egt_degf for egt-degf to have consistent naming
 354 // TODO: raise log-level to ALERT in summer 2010,
 355 // remove alias in fall 2010,
 356 // remove this code in winter 2010
 357     for (unsigned int i=0; i < Propulsion->GetNumEngines(); i++) {
 358       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 359       SGPropertyNode * egtn = node->getNode( "egt_degf" );
 360       if( egtn != NULL ) {
 361         SG_LOG(SG_FLIGHT,SG_WARN,
 362                "Aircraft uses deprecated node egt_degf. Please upgrade to egt-degf");
 363         node->getNode("egt-degf", true)->alias( egtn );
 364       }
 365     }
 366 // end of egt_degf deprecation patch
 367
 368     if (fgGetBool("/sim/presets/running")) {
 369           for (unsigned int i=0; i < Propulsion->GetNumEngines(); i++) {
 370             SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 371             node->setBoolValue("running", true);
 372             Propulsion->GetEngine(i)->SetRunning(true);
 373           }
 374     }
 375
 376     FCS->SetDfPos( ofNorm, globals->get_controls()->get_flaps() );
 377
 378     common_init();
 379
 380     copy_to_JSBsim();
 381     fdmex->RunIC();     //loop JSBSim once w/o integrating
 382     copy_from_JSBsim(); //update the bus
 383
 384     SG_LOG( SG_FLIGHT, SG_INFO, "  Initialized JSBSim with:" );
 385
 386     switch(fgic->GetSpeedSet()) {
 387     case setned:
 388         SG_LOG(SG_FLIGHT,SG_INFO, "  Vn,Ve,Vd= "
 389                << Propagate->GetVel(FGJSBBase::eNorth) << ", "
 390                << Propagate->GetVel(FGJSBBase::eEast) << ", "
 391                << Propagate->GetVel(FGJSBBase::eDown) << " ft/s");
 392     break;
 393     case setuvw:
 394         SG_LOG(SG_FLIGHT,SG_INFO, "  U,V,W= "
 395                << Propagate->GetUVW(1) << ", "
 396                << Propagate->GetUVW(2) << ", "
 397                << Propagate->GetUVW(3) << " ft/s");
 398     break;
 399     case setmach:
 400         SG_LOG(SG_FLIGHT,SG_INFO, "  Mach: "
 401                << Auxiliary->GetMach() );
 402     break;
 403     case setvc:
 404     default:
 405         SG_LOG(SG_FLIGHT,SG_INFO, "  Indicated Airspeed: "
 406                << Auxiliary->GetVcalibratedKTS() << " knots" );
 407     break;
 408     }
 409
 410     stall_warning->setDoubleValue(0);
 411
 412     SG_LOG( SG_FLIGHT, SG_INFO, "  Bank Angle: "
 413             << Propagate->GetEuler(FGJSBBase::ePhi)*RADTODEG << " deg" );
 414     SG_LOG( SG_FLIGHT, SG_INFO, "  Pitch Angle: "
 415             << Propagate->GetEuler(FGJSBBase::eTht)*RADTODEG << " deg" );
 416     SG_LOG( SG_FLIGHT, SG_INFO, "  True Heading: "
 417             << Propagate->GetEuler(FGJSBBase::ePsi)*RADTODEG << " deg" );
 418     SG_LOG( SG_FLIGHT, SG_INFO, "  Latitude: "
 419             << Propagate->GetLocation().GetLatitudeDeg() << " deg" );
 420     SG_LOG( SG_FLIGHT, SG_INFO, "  Longitude: "
 421             << Propagate->GetLocation().GetLongitudeDeg() << " deg" );
 422     SG_LOG( SG_FLIGHT, SG_INFO, "  Altitude: "
 423             << Propagate->GetAltitudeASL() << " feet" );
 424     SG_LOG( SG_FLIGHT, SG_INFO, "  loaded initial conditions" );
 425
 426     SG_LOG( SG_FLIGHT, SG_INFO, "  set dt" );
 427
 428     SG_LOG( SG_FLIGHT, SG_INFO, "Finished initializing JSBSim" );
 429
 430     SG_LOG( SG_FLIGHT, SG_INFO, "FGControls::get_gear_down()= " <<
 431                                   globals->get_controls()->get_gear_down() );
 432 }
 433
 434 /******************************************************************************/
 435
 436 void FGJSBsim::unbind()
 437 {
 438   fdmex->Unbind();
 439   FGInterface::unbind();
 440 }
 441
 442 /******************************************************************************/
 443
 444 // Run an iteration of the EOM (equations of motion)
 445
 446 void FGJSBsim::update( double dt )
 447 {
 448     if(crashed) {
 449       if(!fgGetBool("/sim/crashed"))
 450         fgSetBool("/sim/crashed", true);
 451       return;
 452     }
 453
 454     if (is_suspended())
 455       return;
 456
 457     int multiloop = _calc_multiloop(dt);
 458
 459     int i;
 460
 461     // Compute the radius of the aircraft. That is the radius of a ball
 462     // where all gear units are in. At the moment it is at least 10ft ...
 463     double acrad = 10.0;
 464     int n_gears = GroundReactions->GetNumGearUnits();
 465     for (i=0; i<n_gears; ++i) {
 466       FGColumnVector3 bl = GroundReactions->GetGearUnit(i)->GetBodyLocation();
 467       double r = bl.Magnitude();
 468       if (acrad < r)
 469         acrad = r;
 470     }
 471
 472     // Compute the potential movement of this aircraft and query for the
 473     // ground in this area.
 474     double groundCacheRadius = acrad + 2*dt*Propagate->GetUVW().Magnitude();
 475     double alt, slr, lat, lon;
 476     FGLocation cart = Auxiliary->GetLocationVRP();
 477     if ( needTrim && startup_trim->getBoolValue() ) {
 478       alt = fgic->GetAltitudeASLFtIC();
 479       slr = fgic->GetSeaLevelRadiusFtIC();
 480       lat = fgic->GetLatitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 481       lon = fgic->GetLongitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 482       cart = FGLocation(lon, lat, alt+slr);
 483     }
 484     double cart_pos[3] = { cart(1), cart(2), cart(3) };
 485     double t0 = fdmex->GetSimTime();
 486     bool cache_ok = prepare_ground_cache_ft( t0, t0 + dt, cart_pos,
 487                                              groundCacheRadius );
 488     if (!cache_ok) {
 489       SG_LOG(SG_FLIGHT, SG_WARN,
 490              "FGInterface is being called without scenery below the aircraft!");
 491
 492       alt = fgic->GetAltitudeASLFtIC();
 493       SG_LOG(SG_FLIGHT, SG_WARN, "altitude         = " << alt);
 494
 495       slr = fgic->GetSeaLevelRadiusFtIC();
 496       SG_LOG(SG_FLIGHT, SG_WARN, "sea level radius = " << slr);
 497
 498       lat = fgic->GetLatitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 499       SG_LOG(SG_FLIGHT, SG_WARN, "latitude         = " << lat);
 500
 501       lon = fgic->GetLongitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 502       SG_LOG(SG_FLIGHT, SG_WARN, "longitude        = " << lon);
 503       //return;
 504     }
 505
 506     copy_to_JSBsim();
 507
 508     trimmed->setBoolValue(false);
 509
 510     if ( needTrim ) {
 511       if ( startup_trim->getBoolValue() ) {
 512         double contact[3], d[3], vel[3], agl;
 513         get_agl_ft(fdmex->GetSimTime(), cart_pos, SG_METER_TO_FEET*2, contact,
 514                    d, vel, d, &agl);
 515         double terrain_alt = sqrt(contact[0]*contact[0] + contact[1]*contact[1]
 516              + contact[2]*contact[2]) - fgic->GetSeaLevelRadiusFtIC();
 517
 518         SG_LOG(SG_FLIGHT, SG_INFO,
 519           "Ready to trim, terrain elevation is: "
 520             << terrain_alt * SG_METER_TO_FEET );
 521
 522         if (fgGetBool("/sim/presets/onground")) {
 523           FGColumnVector3 gndVelNED = cart.GetTec2l()
 524                                     * FGColumnVector3(vel[0], vel[1], vel[2]);
 525           fgic->SetVNorthFpsIC(gndVelNED(1));
 526           fgic->SetVEastFpsIC(gndVelNED(2));
 527           fgic->SetVDownFpsIC(gndVelNED(3));
 528         }
 529         fgic->SetTerrainElevationFtIC( terrain_alt );
 530         do_trim();
 531       } else {
 532         fdmex->RunIC();  //apply any changes made through the set_ functions
 533       }
 534       needTrim = false;
 535     }
 536
 537     for ( i=0; i < multiloop; i++ ) {
 538       fdmex->Run();
 539       update_external_forces(fdmex->GetSimTime() + i * fdmex->GetDeltaT());
 540     }
 541
 542     FGJSBBase::Message* msg;
 543     while ((msg = fdmex->ProcessNextMessage()) != NULL) {
 544 //      msg = fdmex->ProcessNextMessage();
 545       switch (msg->type) {
 546       case FGJSBBase::Message::eText:
 547         if (msg->text == "Crash Detected: Simulation FREEZE.")
 548           crashed = true;
 549         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text );
 550         break;
 551       case FGJSBBase::Message::eBool:
 552         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->bVal );
 553         break;
 554       case FGJSBBase::Message::eInteger:
 555         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->iVal );
 556         break;
 557       case FGJSBBase::Message::eDouble:
 558         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->dVal );
 559         break;
 560       default:
 561         SG_LOG( SG_FLIGHT, SG_INFO, "Unrecognized message type." );
 562         break;
 563       }
 564     }
 565
 566     // translate JSBsim back to FG structure so that the
 567     // autopilot (and the rest of the sim can use the updated values
 568     copy_from_JSBsim();
 569 }
 570
 571 /******************************************************************************/
 572
 573 // Convert from the FGInterface struct to the JSBsim generic_ struct
 574
 575 bool FGJSBsim::copy_to_JSBsim()
 576 {
 577     double tmp;
 578     unsigned int i;
 579
 580     // copy control positions into the JSBsim structure
 581
 582     FCS->SetDaCmd( globals->get_controls()->get_aileron());
 583     FCS->SetRollTrimCmd( globals->get_controls()->get_aileron_trim() );
 584     FCS->SetDeCmd( globals->get_controls()->get_elevator());
 585     FCS->SetPitchTrimCmd( globals->get_controls()->get_elevator_trim() );
 586     FCS->SetDrCmd( -globals->get_controls()->get_rudder() );
 587     FCS->SetYawTrimCmd( -globals->get_controls()->get_rudder_trim() );
 588     FCS->SetDsCmd( globals->get_controls()->get_rudder() );
 589     FCS->SetDfCmd( globals->get_controls()->get_flaps() );
 590     FCS->SetDsbCmd( globals->get_controls()->get_speedbrake() );
 591     FCS->SetDspCmd( globals->get_controls()->get_spoilers() );
 592
 593         // Parking brake sets minimum braking
 594         // level for mains.
 595     double parking_brake = globals->get_controls()->get_brake_parking();
 596     double left_brake = globals->get_controls()->get_brake_left();
 597     double right_brake = globals->get_controls()->get_brake_right();
 598
 599     if (ab_brake_engaged->getBoolValue()) {
 600       left_brake = ab_brake_left_pct->getDoubleValue();
 601       right_brake = ab_brake_right_pct->getDoubleValue();
 602     }
 603
 604     FCS->SetLBrake(FMAX(left_brake, parking_brake));
 605     FCS->SetRBrake(FMAX(right_brake, parking_brake));
 606
 607
 608     FCS->SetCBrake( 0.0 );
 609     // FCS->SetCBrake( globals->get_controls()->get_brake(2) );
 610
 611     FCS->SetGearCmd( globals->get_controls()->get_gear_down());
 612     for (i = 0; i < Propulsion->GetNumEngines(); i++) {
 613       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 614
 615       FCS->SetThrottleCmd(i, globals->get_controls()->get_throttle(i));
 616       FCS->SetMixtureCmd(i, globals->get_controls()->get_mixture(i));
 617       FCS->SetPropAdvanceCmd(i, globals->get_controls()->get_prop_advance(i));
 618       FCS->SetFeatherCmd(i, globals->get_controls()->get_feather(i));
 619
 620       switch (Propulsion->GetEngine(i)->GetType()) {
 621       case FGEngine::etPiston:
 622         { // FGPiston code block
 623         FGPiston* eng = (FGPiston*)Propulsion->GetEngine(i);
 624         eng->SetMagnetos( globals->get_controls()->get_magnetos(i) );
 625         break;
 626         } // end FGPiston code block
 627       case FGEngine::etTurbine:
 628         { // FGTurbine code block
 629         FGTurbine* eng = (FGTurbine*)Propulsion->GetEngine(i);
 630         eng->SetAugmentation( globals->get_controls()->get_augmentation(i) );
 631         eng->SetReverse( globals->get_controls()->get_reverser(i) );
 632         //eng->SetInjection( globals->get_controls()->get_water_injection(i) );
 633         eng->SetCutoff( globals->get_controls()->get_cutoff(i) );
 634         eng->SetIgnition( globals->get_controls()->get_ignition(i) );
 635         break;
 636         } // end FGTurbine code block
 637       case FGEngine::etRocket:
 638         { // FGRocket code block
 639 //        FGRocket* eng = (FGRocket*)Propulsion->GetEngine(i);
 640         break;
 641         } // end FGRocket code block
 642       case FGEngine::etTurboprop:
 643         { // FGTurboProp code block
 644         FGTurboProp* eng = (FGTurboProp*)Propulsion->GetEngine(i);
 645         eng->SetReverse( globals->get_controls()->get_reverser(i) );
 646         eng->SetCutoff( globals->get_controls()->get_cutoff(i) );
 647         eng->SetIgnition( globals->get_controls()->get_ignition(i) );
 648
 649         eng->SetGeneratorPower( globals->get_controls()->get_generator_breaker(i) );
 650         eng->SetCondition( globals->get_controls()->get_condition(i) );
 651         break;
 652         } // end FGTurboProp code block
 653       default:
 654         break;
 655       }
 656
 657       { // FGEngine code block
 658       FGEngine* eng = Propulsion->GetEngine(i);
 659
 660       eng->SetStarter( globals->get_controls()->get_starter(i) );
 661       eng->SetRunning( node->getBoolValue("running") );
 662       } // end FGEngine code block
 663     }
 664
 665
 666     Propagate->SetSeaLevelRadius( get_Sea_level_radius() );
 667
 668     Atmosphere->SetExTemperature(
 669                   9.0/5.0*(temperature->getDoubleValue()+273.15) );
 670     Atmosphere->SetExPressure(pressure->getDoubleValue()*70.726566);
 671     Atmosphere->SetExDensity(density->getDoubleValue());
 672
 673     tmp = turbulence_gain->getDoubleValue();
 674     //Atmosphere->SetTurbGain(tmp * tmp * 100.0);
 675
 676     tmp = turbulence_rate->getDoubleValue();
 677     //Atmosphere->SetTurbRate(tmp);
 678
 679     Atmosphere->SetWindNED( -wind_from_north->getDoubleValue(),
 680                             -wind_from_east->getDoubleValue(),
 681                             -wind_from_down->getDoubleValue() );
 682 //    SG_LOG(SG_FLIGHT,SG_INFO, "Wind NED: "
 683 //                  << get_V_north_airmass() << ", "
 684 //                  << get_V_east_airmass()  << ", "
 685 //                  << get_V_down_airmass() );
 686
 687     for (i = 0; i < Propulsion->GetNumTanks(); i++) {
 688       SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
 689       FGTank * tank = Propulsion->GetTank(i);
 690       double fuelDensity = node->getDoubleValue("density-ppg");
 691
 692       if (fuelDensity < 0.1)
 693         fuelDensity = 6.0; // Use average fuel value
 694
 695       tank->SetDensity(fuelDensity);
 696       tank->SetContents(node->getDoubleValue("level-lbs"));
 697     }
 698
 699     Propulsion->SetFuelFreeze((fgGetNode("/sim/freeze/fuel",true))->getBoolValue());
 700     fdmex->SetChild(slaved->getBoolValue());
 701
 702     return true;
 703 }
 704
 705 /******************************************************************************/
 706
 707 // Convert from the JSBsim generic_ struct to the FGInterface struct
 708
 709 bool FGJSBsim::copy_from_JSBsim()
 710 {
 711     unsigned int i, j;
 712 /*
 713     _set_Inertias( MassBalance->GetMass(),
 714                    MassBalance->GetIxx(),
 715                    MassBalance->GetIyy(),
 716                    MassBalance->GetIzz(),
 717                    MassBalance->GetIxz() );
 718 */
 719     _set_CG_Position( MassBalance->GetXYZcg(1),
 720                       MassBalance->GetXYZcg(2),
 721                       MassBalance->GetXYZcg(3) );
 722
 723     _set_Accels_Body( Aircraft->GetBodyAccel(1),
 724                       Aircraft->GetBodyAccel(2),
 725                       Aircraft->GetBodyAccel(3) );
 726
 727     _set_Accels_CG_Body_N ( Aircraft->GetNcg(1),
 728                             Aircraft->GetNcg(2),
 729                             Aircraft->GetNcg(3) );
 730
 731     _set_Accels_Pilot_Body( Auxiliary->GetPilotAccel(1),
 732                             Auxiliary->GetPilotAccel(2),
 733                             Auxiliary->GetPilotAccel(3) );
 734
 735     _set_Nlf( Aircraft->GetNlf() );
 736
 737     // Velocities
 738
 739     _set_Velocities_Local( Propagate->GetVel(FGJSBBase::eNorth),
 740                            Propagate->GetVel(FGJSBBase::eEast),
 741                            Propagate->GetVel(FGJSBBase::eDown) );
 742
 743     _set_Velocities_Wind_Body( Propagate->GetUVW(1),
 744                                Propagate->GetUVW(2),
 745                                Propagate->GetUVW(3) );
 746
 747     // Make the HUD work ...
 748     _set_Velocities_Ground( Propagate->GetVel(FGJSBBase::eNorth),
 749                             Propagate->GetVel(FGJSBBase::eEast),
 750                             -Propagate->GetVel(FGJSBBase::eDown) );
 751
 752     _set_V_rel_wind( Auxiliary->GetVt() );
 753
 754     _set_V_equiv_kts( Auxiliary->GetVequivalentKTS() );
 755
 756     _set_V_calibrated_kts( Auxiliary->GetVcalibratedKTS() );
 757
 758     _set_V_ground_speed( Auxiliary->GetVground() );
 759
 760     _set_Omega_Body( Propagate->GetPQR(FGJSBBase::eP),
 761                      Propagate->GetPQR(FGJSBBase::eQ),
 762                      Propagate->GetPQR(FGJSBBase::eR) );
 763
 764     _set_Euler_Rates( Auxiliary->GetEulerRates(FGJSBBase::ePhi),
 765                       Auxiliary->GetEulerRates(FGJSBBase::eTht),
 766                       Auxiliary->GetEulerRates(FGJSBBase::ePsi) );
 767
 768     _set_Mach_number( Auxiliary->GetMach() );
 769
 770     // Positions of Visual Reference Point
 771     FGLocation l = Auxiliary->GetLocationVRP();
 772     _updateGeocentricPosition( l.GetLatitude(), l.GetLongitude(),
 773                                l.GetRadius() - get_Sea_level_radius() );
 774
 775     _set_Altitude_AGL( Propagate->GetDistanceAGL() );
 776     {
 777       double loc_cart[3] = { l(FGJSBBase::eX), l(FGJSBBase::eY), l(FGJSBBase::eZ) };
 778       double contact[3], d[3], sd, t;
 779       is_valid_m(&t, d, &sd);
 780       get_agl_ft(t, loc_cart, SG_METER_TO_FEET*2, contact, d, d, d, &sd);
 781       double rwrad
 782         = FGColumnVector3( contact[0], contact[1], contact[2] ).Magnitude();
 783       _set_Runway_altitude( rwrad - get_Sea_level_radius() );
 784     }
 785
 786     _set_Euler_Angles( Propagate->GetEuler(FGJSBBase::ePhi),
 787                        Propagate->GetEuler(FGJSBBase::eTht),
 788                        Propagate->GetEuler(FGJSBBase::ePsi) );
 789
 790     _set_Alpha( Auxiliary->Getalpha() );
 791     _set_Beta( Auxiliary->Getbeta() );
 792
 793
 794     _set_Gamma_vert_rad( Auxiliary->GetGamma() );
 795
 796     _set_Earth_position_angle( Inertial->GetEarthPositionAngle() );
 797
 798     _set_Climb_Rate( Propagate->Gethdot() );
 799
 800     const FGMatrix33& Tl2b = Propagate->GetTl2b();
 801     for ( i = 1; i <= 3; i++ ) {
 802         for ( j = 1; j <= 3; j++ ) {
 803             _set_T_Local_to_Body( i, j, Tl2b(i,j) );
 804         }
 805     }
 806
 807     // Copy the engine values from JSBSim.
 808     for ( i=0; i < Propulsion->GetNumEngines(); i++ ) {
 809       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 810       SGPropertyNode * tnode = node->getChild("thruster", 0, true);
 811       FGThruster * thruster = Propulsion->GetEngine(i)->GetThruster();
 812
 813       switch (Propulsion->GetEngine(i)->GetType()) {
 814       case FGEngine::etPiston:
 815         { // FGPiston code block
 816         FGPiston* eng = (FGPiston*)Propulsion->GetEngine(i);
 817         node->setDoubleValue("egt-degf", eng->getExhaustGasTemp_degF());
 818         node->setDoubleValue("oil-temperature-degf", eng->getOilTemp_degF());
 819         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
 820         node->setDoubleValue("mp-osi", eng->getManifoldPressure_inHg());
 821         // NOTE: mp-osi is not in ounces per square inch.
 822         // This error is left for reasons of backwards compatibility with
 823         // existing FlightGear sound and instrument configurations.
 824         node->setDoubleValue("mp-inhg", eng->getManifoldPressure_inHg());
 825         node->setDoubleValue("cht-degf", eng->getCylinderHeadTemp_degF());
 826         node->setDoubleValue("rpm", eng->getRPM());
 827         } // end FGPiston code block
 828         break;
 829       case FGEngine::etRocket:
 830         { // FGRocket code block
 831 //        FGRocket* eng = (FGRocket*)Propulsion->GetEngine(i);
 832         } // end FGRocket code block
 833         break;
 834       case FGEngine::etTurbine:
 835         { // FGTurbine code block
 836         FGTurbine* eng = (FGTurbine*)Propulsion->GetEngine(i);
 837         node->setDoubleValue("n1", eng->GetN1());
 838         node->setDoubleValue("n2", eng->GetN2());
 839         node->setDoubleValue("egt-degf", 32 + eng->GetEGT()*9/5);
 840         node->setBoolValue("augmentation", eng->GetAugmentation());
 841         node->setBoolValue("water-injection", eng->GetInjection());
 842         node->setBoolValue("ignition", eng->GetIgnition());
 843         node->setDoubleValue("nozzle-pos-norm", eng->GetNozzle());
 844         node->setDoubleValue("inlet-pos-norm", eng->GetInlet());
 845         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
 846         node->setBoolValue("reversed", eng->GetReversed());
 847         node->setBoolValue("cutoff", eng->GetCutoff());
 848         node->setDoubleValue("epr", eng->GetEPR());
 849         globals->get_controls()->set_reverser(i, eng->GetReversed() );
 850         globals->get_controls()->set_cutoff(i, eng->GetCutoff() );
 851         globals->get_controls()->set_water_injection(i, eng->GetInjection() );
 852         globals->get_controls()->set_augmentation(i, eng->GetAugmentation() );
 853         } // end FGTurbine code block
 854         break;
 855       case FGEngine::etTurboprop:
 856         { // FGTurboProp code block
 857         FGTurboProp* eng = (FGTurboProp*)Propulsion->GetEngine(i);
 858         node->setDoubleValue("n1", eng->GetN1());
 859         //node->setDoubleValue("n2", eng->GetN2());
 860         node->setDoubleValue("itt_degf", 32 + eng->GetITT()*9/5);
 861         node->setBoolValue("ignition", eng->GetIgnition());
 862         node->setDoubleValue("nozzle-pos-norm", eng->GetNozzle());
 863         node->setDoubleValue("inlet-pos-norm", eng->GetInlet());
 864         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
 865         node->setBoolValue("reversed", eng->GetReversed());
 866         node->setBoolValue("cutoff", eng->GetCutoff());
 867         node->setBoolValue("starting", eng->GetEngStarting());
 868         node->setBoolValue("generator-power", eng->GetGeneratorPower());
 869         node->setBoolValue("damaged", eng->GetCondition());
 870         node->setBoolValue("ielu-intervent", eng->GetIeluIntervent());
 871         node->setDoubleValue("oil-temperature-degf", eng->getOilTemp_degF());
 872 //        node->setBoolValue("onfire", eng->GetFire());
 873         globals->get_controls()->set_reverser(i, eng->GetReversed() );
 874         globals->get_controls()->set_cutoff(i, eng->GetCutoff() );
 875         } // end FGTurboProp code block
 876         break;
 877       case FGEngine::etElectric:
 878         { // FGElectric code block
 879         FGElectric* eng = (FGElectric*)Propulsion->GetEngine(i);
 880         node->setDoubleValue("rpm", eng->getRPM());
 881         } // end FGElectric code block
 882         break;
 883       case FGEngine::etUnknown:
 884         break;
 885       }
 886
 887       { // FGEngine code block
 888       FGEngine* eng = Propulsion->GetEngine(i);
 889       node->setDoubleValue("fuel-flow-gph", eng->getFuelFlow_gph());
 890       node->setDoubleValue("thrust_lb", thruster->GetThrust());
 891       node->setDoubleValue("fuel-flow_pph", eng->getFuelFlow_pph());
 892       node->setBoolValue("running", eng->GetRunning());
 893       node->setBoolValue("starter", eng->GetStarter());
 894       node->setBoolValue("cranking", eng->GetCranking());
 895       globals->get_controls()->set_starter(i, eng->GetStarter() );
 896       } // end FGEngine code block
 897
 898       switch (thruster->GetType()) {
 899       case FGThruster::ttNozzle:
 900         { // FGNozzle code block
 901 //        FGNozzle* noz = (FGNozzle*)thruster;
 902         } // end FGNozzle code block
 903         break;
 904       case FGThruster::ttPropeller:
 905         { // FGPropeller code block
 906         FGPropeller* prop = (FGPropeller*)thruster;
 907         tnode->setDoubleValue("rpm", thruster->GetRPM());
 908         tnode->setDoubleValue("pitch", prop->GetPitch());
 909         tnode->setDoubleValue("torque", prop->GetTorque());
 910         tnode->setBoolValue("feathered", prop->GetFeather());
 911         } // end FGPropeller code block
 912         break;
 913       case FGThruster::ttRotor:
 914         { // FGRotor code block
 915 //        FGRotor* rotor = (FGRotor*)thruster;
 916         } // end FGRotor code block
 917         break;
 918       case FGThruster::ttDirect:
 919         { // Direct code block
 920         } // end Direct code block
 921         break;
 922       }
 923
 924     }
 925
 926     // Copy the fuel levels from JSBSim if fuel
 927     // freeze not enabled.
 928     if ( ! Propulsion->GetFuelFreeze() ) {
 929       for (i = 0; i < Propulsion->GetNumTanks(); i++) {
 930         SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
 931         FGTank* tank = Propulsion->GetTank(i);
 932         double contents = tank->GetContents();
 933         double temp = tank->GetTemperature_degC();
 934         double fuelDensity = tank->GetDensity();
 935
 936         if (fuelDensity < 0.1)
 937           fuelDensity = 6.0; // Use average fuel value
 938
 939         node->setDoubleValue("density-ppg" , fuelDensity);
 940         node->setDoubleValue("level-lbs", contents);
 941         if (temp != -9999.0) node->setDoubleValue("temperature_degC", temp);
 942       }
 943     }
 944
 945     update_gear();
 946
 947     stall_warning->setDoubleValue( Aerodynamics->GetStallWarn() );
 948
 949     elevator_pos_pct->setDoubleValue( FCS->GetDePos(ofNorm) );
 950     left_aileron_pos_pct->setDoubleValue( FCS->GetDaLPos(ofNorm) );
 951     right_aileron_pos_pct->setDoubleValue( FCS->GetDaRPos(ofNorm) );
 952     rudder_pos_pct->setDoubleValue( -1*FCS->GetDrPos(ofNorm) );
 953     flap_pos_pct->setDoubleValue( FCS->GetDfPos(ofNorm) );
 954     speedbrake_pos_pct->setDoubleValue( FCS->GetDsbPos(ofNorm) );
 955     spoilers_pos_pct->setDoubleValue( FCS->GetDspPos(ofNorm) );
 956     tailhook_pos_pct->setDoubleValue( FCS->GetTailhookPos() );
 957     wing_fold_pos_pct->setDoubleValue( FCS->GetWingFoldPos() );
 958
 959     // force a sim crashed if crashed (altitude AGL < 0)
 960     if (get_Altitude_AGL() < -100.0) {
 961          fdmex->SuspendIntegration();
 962          crashed = true;
 963     }
 964
 965     return true;
 966 }
 967
 968
 969 bool FGJSBsim::ToggleDataLogging(void)
 970 {
 971   // ToDo: handle this properly
 972   fdmex->DisableOutput();
 973   return false;
 974 }
 975
 976
 977 bool FGJSBsim::ToggleDataLogging(bool state)
 978 {
 979     if (state) {
 980       fdmex->EnableOutput();
 981       return true;
 982     } else {
 983       fdmex->DisableOutput();
 984       return false;
 985     }
 986 }
 987
 988
 989 //Positions
 990 void FGJSBsim::set_Latitude(double lat)
 991 {
 992     static SGConstPropertyNode_ptr altitude = fgGetNode("/position/altitude-ft");
 993     double alt;
 994     double sea_level_radius_meters, lat_geoc;
 995
 996     // In case we're not trimming
 997     FGInterface::set_Latitude(lat);
 998
 999     if ( altitude->getDoubleValue() > -9990 ) {
1000       alt = altitude->getDoubleValue();
1001     } else {
1002       alt = 0.0;
1003     }
1004
1005     update_ic();
1006     SG_LOG(SG_FLIGHT,SG_INFO,"FGJSBsim::set_Latitude: " << lat );
1007     SG_LOG(SG_FLIGHT,SG_INFO," cur alt (ft) =  " << alt );
1008
1009     sgGeodToGeoc( lat, alt * SG_FEET_TO_METER,
1010                       &sea_level_radius_meters, &lat_geoc );
1011     _set_Sea_level_radius( sea_level_radius_meters * SG_METER_TO_FEET  );
1012     fgic->SetSeaLevelRadiusFtIC( sea_level_radius_meters * SG_METER_TO_FEET  );
1013     fgic->SetLatitudeRadIC( lat_geoc );
1014     needTrim=true;
1015 }
1016
1017
1018 void FGJSBsim::set_Longitude(double lon)
1019 {
1020     SG_LOG(SG_FLIGHT,SG_INFO,"FGJSBsim::set_Longitude: " << lon );
1021
1022     // In case we're not trimming
1023     FGInterface::set_Longitude(lon);
1024
1025     update_ic();
1026     fgic->SetLongitudeRadIC( lon );
1027     needTrim=true;
1028 }
1029
1030 // Sets the altitude above sea level.
1031 void FGJSBsim::set_Altitude(double alt)
1032 {
1033     static SGConstPropertyNode_ptr latitude = fgGetNode("/position/latitude-deg");
1034
1035     double sea_level_radius_meters,lat_geoc;
1036
1037     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Altitude: " << alt );
1038     SG_LOG(SG_FLIGHT,SG_INFO, "  lat (deg) = " << latitude->getDoubleValue() );
1039
1040     // In case we're not trimming
1041     FGInterface::set_Altitude(alt);
1042
1043     update_ic();
1044     sgGeodToGeoc( latitude->getDoubleValue() * SGD_DEGREES_TO_RADIANS, alt,
1045                   &sea_level_radius_meters, &lat_geoc);
1046     _set_Sea_level_radius( sea_level_radius_meters * SG_METER_TO_FEET  );
1047     fgic->SetSeaLevelRadiusFtIC( sea_level_radius_meters * SG_METER_TO_FEET );
1048     SG_LOG(SG_FLIGHT, SG_INFO,
1049           "Terrain elevation: " << FGInterface::get_Runway_altitude() * SG_METER_TO_FEET );
1050     fgic->SetLatitudeRadIC( lat_geoc );
1051     fgic->SetAltitudeASLFtIC(alt);
1052     needTrim=true;
1053 }
1054
1055 void FGJSBsim::set_V_calibrated_kts(double vc)
1056 {
1057     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_V_calibrated_kts: " <<  vc );
1058
1059     // In case we're not trimming
1060     FGInterface::set_V_calibrated_kts(vc);
1061
1062     update_ic();
1063     fgic->SetVcalibratedKtsIC(vc);
1064     needTrim=true;
1065 }
1066
1067 void FGJSBsim::set_Mach_number(double mach)
1068 {
1069     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Mach_number: " <<  mach );
1070
1071     // In case we're not trimming
1072     FGInterface::set_Mach_number(mach);
1073
1074     update_ic();
1075     fgic->SetMachIC(mach);
1076     needTrim=true;
1077 }
1078
1079 void FGJSBsim::set_Velocities_Local( double north, double east, double down )
1080 {
1081     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Velocities_Local: "
1082        << north << ", " <<  east << ", " << down );
1083
1084     // In case we're not trimming
1085     FGInterface::set_Velocities_Local(north, east, down);
1086
1087     update_ic();
1088     fgic->SetVNorthFpsIC(north);
1089     fgic->SetVEastFpsIC(east);
1090     fgic->SetVDownFpsIC(down);
1091     needTrim=true;
1092 }
1093
1094 void FGJSBsim::set_Velocities_Wind_Body( double u, double v, double w)
1095 {
1096     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Velocities_Wind_Body: "
1097        << u << ", " <<  v << ", " <<  w );
1098
1099     // In case we're not trimming
1100     FGInterface::set_Velocities_Wind_Body(u, v, w);
1101
1102     update_ic();
1103     fgic->SetUBodyFpsIC(u);
1104     fgic->SetVBodyFpsIC(v);
1105     fgic->SetWBodyFpsIC(w);
1106     needTrim=true;
1107 }
1108
1109 //Euler angles
1110 void FGJSBsim::set_Euler_Angles( double phi, double theta, double psi )
1111 {
1112     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Euler_Angles: "
1113        << phi << ", " << theta << ", " << psi );
1114
1115     // In case we're not trimming
1116     FGInterface::set_Euler_Angles(phi, theta, psi);
1117
1118     update_ic();
1119     fgic->SetThetaRadIC(theta);
1120     fgic->SetPhiRadIC(phi);
1121     fgic->SetPsiRadIC(psi);
1122     needTrim=true;
1123 }
1124
1125 //Flight Path
1126 void FGJSBsim::set_Climb_Rate( double roc)
1127 {
1128     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Climb_Rate: " << roc );
1129
1130     // In case we're not trimming
1131     FGInterface::set_Climb_Rate(roc);
1132
1133     update_ic();
1134     //since both climb rate and flight path angle are set in the FG
1135     //startup sequence, something is needed to keep one from cancelling
1136     //out the other.
1137     if( !(fabs(roc) > 1 && fabs(fgic->GetFlightPathAngleRadIC()) < 0.01) ) {
1138       fgic->SetClimbRateFpsIC(roc);
1139     }
1140     needTrim=true;
1141 }
1142
1143 void FGJSBsim::set_Gamma_vert_rad( double gamma)
1144 {
1145     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Gamma_vert_rad: " << gamma );
1146
1147     update_ic();
1148     if( !(fabs(gamma) < 0.01 && fabs(fgic->GetClimbRateFpsIC()) > 1) ) {
1149       fgic->SetFlightPathAngleRadIC(gamma);
1150     }
1151     needTrim=true;
1152 }
1153
1154 void FGJSBsim::init_gear(void )
1155 {
1156     FGGroundReactions* gr=fdmex->GetGroundReactions();
1157     int Ngear=GroundReactions->GetNumGearUnits();
1158     for (int i=0;i<Ngear;i++) {
1159       FGLGear *gear = gr->GetGearUnit(i);
1160       SGPropertyNode * node = fgGetNode("gear/gear", i, true);
1161       node->setDoubleValue("xoffset-in", gear->GetBodyLocation()(1));
1162       node->setDoubleValue("yoffset-in", gear->GetBodyLocation()(2));
1163       node->setDoubleValue("zoffset-in", gear->GetBodyLocation()(3));
1164       node->setBoolValue("wow", gear->GetWOW());
1165       node->setDoubleValue("rollspeed-ms", gear->GetWheelRollVel()*0.3043);
1166       node->setBoolValue("has-brake", gear->GetBrakeGroup() > 0);
1167       node->setDoubleValue("position-norm", gear->GetGearUnitPos());
1168       node->setDoubleValue("tire-pressure-norm", gear->GetTirePressure());
1169       node->setDoubleValue("compression-norm", gear->GetCompLen());
1170       node->setDoubleValue("compression-ft", gear->GetCompLen());
1171       if ( gear->GetSteerable() )
1172         node->setDoubleValue("steering-norm", gear->GetSteerNorm());
1173     }
1174 }
1175
1176 void FGJSBsim::update_gear(void)
1177 {
1178     FGGroundReactions* gr=fdmex->GetGroundReactions();
1179     int Ngear=GroundReactions->GetNumGearUnits();
1180     for (int i=0;i<Ngear;i++) {
1181       FGLGear *gear = gr->GetGearUnit(i);
1182       SGPropertyNode * node = fgGetNode("gear/gear", i, true);
1183       node->getChild("wow", 0, true)->setBoolValue( gear->GetWOW());
1184       node->getChild("rollspeed-ms", 0, true)->setDoubleValue(gear->GetWheelRollVel()*0.3043);
1185       node->getChild("position-norm", 0, true)->setDoubleValue(gear->GetGearUnitPos());
1186       gear->SetTirePressure(node->getDoubleValue("tire-pressure-norm"));
1187       node->setDoubleValue("compression-norm", gear->GetCompLen());
1188       node->setDoubleValue("compression-ft", gear->GetCompLen());
1189       if ( gear->GetSteerable() )
1190         node->setDoubleValue("steering-norm", gear->GetSteerNorm());
1191     }
1192 }
1193
1194 void FGJSBsim::do_trim(void)
1195 {
1196   FGTrim *fgtrim;
1197
1198   if ( fgGetBool("/sim/presets/onground") )
1199   {
1200     fgtrim = new FGTrim(fdmex,tGround);
1201   } else {
1202     fgtrim = new FGTrim(fdmex,tLongitudinal);
1203   }
1204
1205   if ( !fgtrim->DoTrim() ) {
1206     fgtrim->Report();
1207     fgtrim->TrimStats();
1208   } else {
1209     trimmed->setBoolValue(true);
1210   }
1211   delete fgtrim;
1212
1213   pitch_trim->setDoubleValue( FCS->GetPitchTrimCmd() );
1214   throttle_trim->setDoubleValue( FCS->GetThrottleCmd(0) );
1215   aileron_trim->setDoubleValue( FCS->GetDaCmd() );
1216   rudder_trim->setDoubleValue( FCS->GetDrCmd() );
1217
1218   globals->get_controls()->set_elevator_trim(FCS->GetPitchTrimCmd());
1219   globals->get_controls()->set_elevator(FCS->GetDeCmd());
1220   globals->get_controls()->set_throttle(FGControls::ALL_ENGINES,
1221   FCS->GetThrottleCmd(0));
1222
1223   globals->get_controls()->set_aileron(FCS->GetDaCmd());
1224   globals->get_controls()->set_rudder( FCS->GetDrCmd());
1225
1226   SG_LOG( SG_FLIGHT, SG_INFO, "  Trim complete" );
1227 }
1228
1229 void FGJSBsim::update_ic(void)
1230 {
1231    if ( !needTrim ) {
1232      fgic->SetLatitudeRadIC(get_Lat_geocentric() );
1233      fgic->SetLongitudeRadIC( get_Longitude() );
1234      fgic->SetAltitudeASLFtIC( get_Altitude() );
1235      fgic->SetVcalibratedKtsIC( get_V_calibrated_kts() );
1236      fgic->SetThetaRadIC( get_Theta() );
1237      fgic->SetPhiRadIC( get_Phi() );
1238      fgic->SetPsiRadIC( get_Psi() );
1239      fgic->SetClimbRateFpsIC( get_Climb_Rate() );
1240    }
1241 }
1242
1243 bool
1244 FGJSBsim::get_agl_ft(double t, const double pt[3], double alt_off,
1245                      double contact[3], double normal[3], double vel[3],
1246                      double angularVel[3], double *agl)
1247 {
1248    const SGMaterial* material;
1249    simgear::BVHNode::Id id;
1250    if (!FGInterface::get_agl_ft(t, pt, alt_off, contact, normal, vel,
1251                                 angularVel, material, id))
1252        return false;
1253    SGGeod geodPt = SGGeod::fromCart(SG_FEET_TO_METER*SGVec3d(pt));
1254    SGQuatd hlToEc = SGQuatd::fromLonLat(geodPt);
1255    *agl = dot(hlToEc.rotate(SGVec3d(0, 0, 1)), SGVec3d(contact) - SGVec3d(pt));
1256    return true;
1257 }
1258
1259 inline static double dot3(const FGColumnVector3& a, const FGColumnVector3& b)
1260 {
1261     return a(1) * b(1) + a(2) * b(2) + a(3) * b(3);
1262 }
1263
1264 inline static double sqr(double x)
1265 {
1266     return x * x;
1267 }
1268
1269 static double angle_diff(double a, double b)
1270 {
1271     double diff = fabs(a - b);
1272     if (diff > 180) diff = 360 - diff;
1273
1274     return diff;
1275 }
1276
1277 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)
1278 {
1279     FGColumnVector3 tip(-hook_length * cos_fi_guess, 0, hook_length * sin_fi_guess);
1280     double dist = dot3(tip, ground_normal_body);
1281     if (fabs(dist + E) < 0.0001) {
1282         sin_fis[*points] = sin_fi_guess;
1283         cos_fis[*points] = cos_fi_guess;
1284         fis[*points] = atan2(sin_fi_guess, cos_fi_guess) * SG_RADIANS_TO_DEGREES;
1285         (*points)++;
1286     }
1287 }
1288
1289
1290 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)
1291 {
1292     if (sin_fi_guess >= -1 && sin_fi_guess <= 1) {
1293         double cos_fi_guess = sqrt(1 - sqr(sin_fi_guess));
1294         check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess, cos_fi_guess, sin_fis, cos_fis, fis, points);
1295         if (fabs(cos_fi_guess) > SG_EPSILON) {
1296             check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess, -cos_fi_guess, sin_fis, cos_fis, fis, points);
1297         }
1298     }
1299 }
1300
1301 void FGJSBsim::update_external_forces(double t_off)
1302 {
1303     const FGMatrix33& Tb2l = Propagate->GetTb2l();
1304     const FGMatrix33& Tl2b = Propagate->GetTl2b();
1305     const FGLocation& Location = Propagate->GetLocation();
1306     const FGMatrix33& Tec2l = Location.GetTec2l();
1307
1308     double hook_area[4][3];
1309
1310     FGColumnVector3 hook_root_body = MassBalance->StructuralToBody(hook_root_struct);
1311     FGColumnVector3 hook_root = Location.LocalToLocation(Tb2l *   hook_root_body);
1312     hook_area[1][0] = hook_root(1);
1313     hook_area[1][1] = hook_root(2);
1314     hook_area[1][2] = hook_root(3);
1315
1316     hook_length = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-length-ft", 6.75);
1317     double fi_min = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-min-deg", -18);
1318     double fi_max = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-max-deg", 30);
1319     double fi = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-norm") * (fi_max - fi_min) + fi_min;
1320     double cos_fi = cos(fi * SG_DEGREES_TO_RADIANS);
1321     double sin_fi = sin(fi * SG_DEGREES_TO_RADIANS);
1322
1323     FGColumnVector3 hook_tip_body = hook_root_body;
1324     hook_tip_body(1) -= hook_length * cos_fi;
1325     hook_tip_body(3) += hook_length * sin_fi;
1326
1327     double contact[3];
1328     double ground_normal[3];
1329     double ground_vel[3];
1330     double ground_angular_vel[3];
1331     double root_agl_ft;
1332
1333     if (!got_wire) {
1334         bool got = get_agl_ft(t_off, hook_area[1], 0, contact, ground_normal,
1335                               ground_vel, ground_angular_vel, &root_agl_ft);
1336         if (got && root_agl_ft > 0 && root_agl_ft < hook_length) {
1337             FGColumnVector3 ground_normal_body = Tl2b * (Tec2l * FGColumnVector3(ground_normal[0], ground_normal[1], ground_normal[2]));
1338             FGColumnVector3 contact_body = Tl2b * Location.LocationToLocal(FGColumnVector3(contact[0], contact[1], contact[2]));
1339             double D = -dot3(contact_body, ground_normal_body);
1340
1341             // check hook tip agl against same ground plane
1342             double hook_tip_agl_ft = dot3(hook_tip_body, ground_normal_body) + D;
1343             if (hook_tip_agl_ft < 0) {
1344
1345                 // hook tip: hx - l cos, hy, hz + l sin
1346                 // on ground:  - n0 l cos + n2 l sin + E = 0
1347
1348                 double E = D + dot3(hook_root_body, ground_normal_body);
1349
1350                 // substitue x = sin fi, cos fi = sqrt(1 - x * x)
1351                 // and rearrange to get a quadratic with coeffs:
1352                 double a = sqr(hook_length) * (sqr(ground_normal_body(1)) + sqr(ground_normal_body(3)));
1353                 double b = 2 * E * ground_normal_body(3) * hook_length;
1354                 double c = sqr(E) - sqr(ground_normal_body(1) * hook_length);
1355
1356                 double disc = sqr(b) - 4 * a * c;
1357                 if (disc >= 0) {
1358                     double delta = sqrt(disc) / (2 * a);
1359
1360                     // allow 4 solutions for safety, should never happen
1361                     double sin_fis[4];
1362                     double cos_fis[4];
1363                     double fis[4];
1364                     int points = 0;
1365
1366                     double sin_fi_guess = -b / (2 * a) - delta;
1367                     check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess, sin_fis, cos_fis, fis, &points);
1368                     check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess + 2 * delta, sin_fis, cos_fis, fis, &points);
1369
1370                     if (points == 2) {
1371                         double diff1 = angle_diff(fi, fis[0]);
1372                         double diff2 = angle_diff(fi, fis[1]);
1373                         int point = diff1 < diff2 ? 0 : 1;
1374                         fi = fis[point];
1375                         sin_fi = sin_fis[point];
1376                         cos_fi = cos_fis[point];
1377                         hook_tip_body(1) = hook_root_body(1) - hook_length * cos_fi;
1378                         hook_tip_body(3) = hook_root_body(3) + hook_length * sin_fi;
1379                     }
1380                 }
1381             }
1382         }
1383     } else {
1384         FGColumnVector3 hook_root_vel = Propagate->GetVel() + (Tb2l * (Propagate->GetPQR() *  hook_root_body));
1385         double wire_ends_ec[2][3];
1386         double wire_vel_ec[2][3];
1387         get_wire_ends_ft(t_off, wire_ends_ec, wire_vel_ec);
1388         FGColumnVector3 wire_vel_1 = Tec2l * FGColumnVector3(wire_vel_ec[0][0], wire_vel_ec[0][1], wire_vel_ec[0][2]);
1389         FGColumnVector3 wire_vel_2 = Tec2l * FGColumnVector3(wire_vel_ec[1][0], wire_vel_ec[1][1], wire_vel_ec[1][2]);
1390         FGColumnVector3 rel_vel = hook_root_vel - (wire_vel_1 + wire_vel_2) / 2;
1391         if (rel_vel.Magnitude() < 3) {
1392             got_wire = false;
1393             release_wire();
1394             fgSetDouble("/fdm/jsbsim/external_reactions/hook/magnitude", 0.0);
1395         } else {
1396             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;
1397             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;
1398             FGColumnVector3 force_plane_normal = wire_end1_body * wire_end2_body;
1399             force_plane_normal.Normalize();
1400             cos_fi = dot3(force_plane_normal, FGColumnVector3(0, 0, 1));
1401             if (cos_fi < 0) cos_fi = -cos_fi;
1402             sin_fi = sqrt(1 - sqr(cos_fi));
1403             fi = atan2(sin_fi, cos_fi) * SG_RADIANS_TO_DEGREES;
1404
1405             fgSetDouble("/fdm/jsbsim/external_reactions/hook/x", -cos_fi);
1406             fgSetDouble("/fdm/jsbsim/external_reactions/hook/y", 0);
1407             fgSetDouble("/fdm/jsbsim/external_reactions/hook/z", sin_fi);
1408             fgSetDouble("/fdm/jsbsim/external_reactions/hook/magnitude", fgGetDouble("/fdm/jsbsim/systems/hook/force"));
1409         }
1410     }
1411
1412     FGColumnVector3 hook_tip = Location.LocalToLocation(Tb2l * hook_tip_body);
1413
1414     hook_area[0][0] = hook_tip(1);
1415     hook_area[0][1] = hook_tip(2);
1416     hook_area[0][2] = hook_tip(3);
1417
1418     if (!got_wire) {
1419         // The previous positions.
1420         hook_area[2][0] = last_hook_root[0];
1421         hook_area[2][1] = last_hook_root[1];
1422         hook_area[2][2] = last_hook_root[2];
1423         hook_area[3][0] = last_hook_tip[0];
1424         hook_area[3][1] = last_hook_tip[1];
1425         hook_area[3][2] = last_hook_tip[2];
1426
1427         // Check if we caught a wire.
1428         // Returns true if we caught one.
1429         if (caught_wire_ft(t_off, hook_area)) {
1430                 got_wire = true;
1431         }
1432     }
1433
1434     // save actual position as old position ...
1435     last_hook_tip[0] = hook_area[0][0];
1436     last_hook_tip[1] = hook_area[0][1];
1437     last_hook_tip[2] = hook_area[0][2];
1438     last_hook_root[0] = hook_area[1][0];
1439     last_hook_root[1] = hook_area[1][1];
1440     last_hook_root[2] = hook_area[1][2];
1441
1442     fgSetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-deg", fi);
1443 }
1444