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
  30 #include <stdio.h>    //    size_t
  31 #include <string>
  32
  33 #include <simgear/constants.h>
  34 #include <simgear/debug/logstream.hxx>
  35 #include <simgear/math/sg_geodesy.hxx>
  36 #include <simgear/misc/sg_path.hxx>
  37 #include <simgear/structure/commands.hxx>
  38
  39 #include <FDM/flight.hxx>
  40
  41 #include <Aircraft/controls.hxx>
  42 #include <Main/globals.hxx>
  43 #include <Main/fg_props.hxx>
  44
  45 #include "JSBSim.hxx"
  46 #include <FDM/JSBSim/FGFDMExec.h>
  47 #include <FDM/JSBSim/FGJSBBase.h>
  48 #include <FDM/JSBSim/initialization/FGInitialCondition.h>
  49 #include <FDM/JSBSim/initialization/FGTrim.h>
  50 #include <FDM/JSBSim/models/FGModel.h>
  51 #include <FDM/JSBSim/models/FGAircraft.h>
  52 #include <FDM/JSBSim/models/FGFCS.h>
  53 #include <FDM/JSBSim/models/FGPropagate.h>
  54 #include <FDM/JSBSim/models/FGAuxiliary.h>
  55 #include <FDM/JSBSim/models/FGInertial.h>
  56 #include <FDM/JSBSim/models/FGAtmosphere.h>
  57 #include <FDM/JSBSim/models/FGMassBalance.h>
  58 #include <FDM/JSBSim/models/FGAerodynamics.h>
  59 #include <FDM/JSBSim/models/FGLGear.h>
  60 #include <FDM/JSBSim/models/FGGroundReactions.h>
  61 #include <FDM/JSBSim/models/FGPropulsion.h>
  62 #include <FDM/JSBSim/models/propulsion/FGEngine.h>
  63 #include <FDM/JSBSim/models/propulsion/FGPiston.h>
  64 #include <FDM/JSBSim/models/propulsion/FGTurbine.h>
  65 #include <FDM/JSBSim/models/propulsion/FGTurboProp.h>
  66 #include <FDM/JSBSim/models/propulsion/FGRocket.h>
  67 #include <FDM/JSBSim/models/propulsion/FGElectric.h>
  68 #include <FDM/JSBSim/models/propulsion/FGNozzle.h>
  69 #include <FDM/JSBSim/models/propulsion/FGPropeller.h>
  70 #include <FDM/JSBSim/models/propulsion/FGRotor.h>
  71 #include <FDM/JSBSim/models/propulsion/FGTank.h>
  72 #include <FDM/JSBSim/input_output/FGPropertyManager.h>
  73 #include <FDM/JSBSim/input_output/FGGroundCallback.h>
  74
  75 using namespace JSBSim;
  76
  77 static inline double
  78 FMAX (double a, double b)
  79 {
  80   return a > b ? a : b;
  81 }
  82
  83 class FGFSGroundCallback : public FGGroundCallback {
  84 public:
  85   FGFSGroundCallback(FGJSBsim* ifc) : mInterface(ifc) {}
  86   virtual ~FGFSGroundCallback() {}
  87
  88   /** Get the altitude above sea level dependent on the location. */
  89   virtual double GetAltitude(const FGLocation& l) const {
  90     double pt[3] = { SG_FEET_TO_METER*l(eX),
  91                      SG_FEET_TO_METER*l(eY),
  92                      SG_FEET_TO_METER*l(eZ) };
  93     double lat, lon, alt;
  94     sgCartToGeod( pt, &lat, &lon, &alt);
  95     return alt * SG_METER_TO_FEET;
  96   }
  97
  98   /** Compute the altitude above ground. */
  99   virtual double GetAGLevel(double t, const FGLocation& l,
 100                             FGLocation& cont, FGColumnVector3& n,
 101                             FGColumnVector3& v, FGColumnVector3& w) const {
 102     double loc_cart[3] = { l(eX), l(eY), l(eZ) };
 103     double contact[3], normal[3], vel[3], angularVel[3], agl = 0;
 104     mInterface->get_agl_ft(t, loc_cart, SG_METER_TO_FEET*2, contact, normal,
 105                            vel, angularVel, &agl);
 106     n = FGColumnVector3( normal[0], normal[1], normal[2] );
 107     v = FGColumnVector3( vel[0], vel[1], vel[2] );
 108     w = FGColumnVector3( angularVel[0], angularVel[1], angularVel[2] );
 109     cont = FGColumnVector3( contact[0], contact[1], contact[2] );
 110     return agl;
 111   }
 112 private:
 113   FGJSBsim* mInterface;
 114 };
 115
 116 /******************************************************************************/
 117
 118 FGJSBsim::FGJSBsim( double dt )
 119   : FGInterface(dt), got_wire(false)
 120 {
 121     bool result;
 122                                 // Set up the debugging level
 123                                 // FIXME: this will not respond to
 124                                 // runtime changes
 125
 126                                 // if flight is excluded, don't bother
 127     if ((logbuf::get_log_classes() & SG_FLIGHT) != 0) {
 128
 129                                 // do a rough-and-ready mapping to
 130                                 // the levels documented in FGFDMExec.h
 131         switch (logbuf::get_log_priority()) {
 132         case SG_BULK:
 133             FGJSBBase::debug_lvl = 0x1f;
 134             break;
 135         case SG_DEBUG:
 136             FGJSBBase::debug_lvl = 0x0f;
 137         case SG_INFO:
 138             FGJSBBase::debug_lvl = 0x01;
 139             break;
 140         case SG_WARN:
 141         case SG_ALERT:
 142             FGJSBBase::debug_lvl = 0x00;
 143             break;
 144         }
 145     }
 146
 147     resetPropertyState();
 148
 149     fdmex = new FGFDMExec( (FGPropertyManager*)globals->get_props() );
 150
 151     // Register ground callback.
 152     fdmex->SetGroundCallback( new FGFSGroundCallback(this) );
 153
 154     Atmosphere      = fdmex->GetAtmosphere();
 155     FCS             = fdmex->GetFCS();
 156     MassBalance     = fdmex->GetMassBalance();
 157     Propulsion      = fdmex->GetPropulsion();
 158     Aircraft        = fdmex->GetAircraft();
 159     Propagate        = fdmex->GetPropagate();
 160     Auxiliary       = fdmex->GetAuxiliary();
 161     Inertial        = fdmex->GetInertial();
 162     Aerodynamics    = fdmex->GetAerodynamics();
 163     GroundReactions = fdmex->GetGroundReactions();
 164
 165     fgic=fdmex->GetIC();
 166     needTrim=true;
 167
 168     SGPath aircraft_path( fgGetString("/sim/aircraft-dir") );
 169
 170     SGPath engine_path( fgGetString("/sim/aircraft-dir") );
 171     engine_path.append( "Engine" );
 172
 173     SGPath systems_path( fgGetString("/sim/aircraft-dir") );
 174     systems_path.append( "Systems" );
 175
 176 // deprecate sim-time-sec for simulation/sim-time-sec
 177 // remove alias with increased configuration file version number (2.1 or later)
 178     SGPropertyNode * node = fgGetNode("/fdm/jsbsim/simulation/sim-time-sec");
 179     fgGetNode("/fdm/jsbsim/sim-time-sec", true)->alias( node );
 180 // end of sim-time-sec deprecation patch
 181
 182     fdmex->Setdt( dt );
 183
 184     result = fdmex->LoadModel( aircraft_path.str(),
 185                                engine_path.str(),
 186                                systems_path.str(),
 187                                fgGetString("/sim/aero"), false );
 188
 189     if (result) {
 190       SG_LOG( SG_FLIGHT, SG_INFO, "  loaded aero.");
 191     } else {
 192       SG_LOG( SG_FLIGHT, SG_INFO,
 193               "  aero does not exist (you may have mis-typed the name).");
 194       throw(-1);
 195     }
 196
 197     SG_LOG( SG_FLIGHT, SG_INFO, "" );
 198     SG_LOG( SG_FLIGHT, SG_INFO, "" );
 199     SG_LOG( SG_FLIGHT, SG_INFO, "After loading aero definition file ..." );
 200
 201     int Neng = Propulsion->GetNumEngines();
 202     SG_LOG( SG_FLIGHT, SG_INFO, "num engines = " << Neng );
 203
 204     if ( GroundReactions->GetNumGearUnits() <= 0 ) {
 205         SG_LOG( SG_FLIGHT, SG_ALERT, "num gear units = "
 206                 << GroundReactions->GetNumGearUnits() );
 207         SG_LOG( SG_FLIGHT, SG_ALERT, "This is a very bad thing because with 0 gear units, the ground trimming");
 208         SG_LOG( SG_FLIGHT, SG_ALERT, "routine (coming up later in the code) will core dump.");
 209         SG_LOG( SG_FLIGHT, SG_ALERT, "Halting the sim now, and hoping a solution will present itself soon!");
 210         exit(-1);
 211     }
 212
 213     init_gear();
 214
 215     // Set initial fuel levels if provided.
 216     for (unsigned int i = 0; i < Propulsion->GetNumTanks(); i++) {
 217       SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
 218       if (node->getChild("level-gal_us", 0, false) != 0) {
 219         Propulsion->GetTank(i)->SetContents(node->getDoubleValue("level-gal_us") * 6.6);
 220       } else {
 221         node->setDoubleValue("level-lbs", Propulsion->GetTank(i)->GetContents());
 222         node->setDoubleValue("level-gal_us", Propulsion->GetTank(i)->GetContents() / 6.6);
 223       }
 224       node->setDoubleValue("capacity-gal_us",
 225                            Propulsion->GetTank(i)->GetCapacity() / 6.6);
 226     }
 227     Propulsion->SetFuelFreeze((fgGetNode("/sim/freeze/fuel",true))->getBoolValue());
 228
 229     fgSetDouble("/fdm/trim/pitch-trim", FCS->GetPitchTrimCmd());
 230     fgSetDouble("/fdm/trim/throttle",   FCS->GetThrottleCmd(0));
 231     fgSetDouble("/fdm/trim/aileron",    FCS->GetDaCmd());
 232     fgSetDouble("/fdm/trim/rudder",     FCS->GetDrCmd());
 233
 234     startup_trim = fgGetNode("/sim/presets/trim", true);
 235
 236     trimmed = fgGetNode("/fdm/trim/trimmed", true);
 237     trimmed->setBoolValue(false);
 238
 239     pitch_trim = fgGetNode("/fdm/trim/pitch-trim", true );
 240     throttle_trim = fgGetNode("/fdm/trim/throttle", true );
 241     aileron_trim = fgGetNode("/fdm/trim/aileron", true );
 242     rudder_trim = fgGetNode("/fdm/trim/rudder", true );
 243
 244     stall_warning = fgGetNode("/sim/alarms/stall-warning",true);
 245     stall_warning->setDoubleValue(0);
 246
 247
 248     flap_pos_pct=fgGetNode("/surface-positions/flap-pos-norm",true);
 249     elevator_pos_pct=fgGetNode("/surface-positions/elevator-pos-norm",true);
 250     left_aileron_pos_pct
 251         =fgGetNode("/surface-positions/left-aileron-pos-norm",true);
 252     right_aileron_pos_pct
 253         =fgGetNode("/surface-positions/right-aileron-pos-norm",true);
 254     rudder_pos_pct=fgGetNode("/surface-positions/rudder-pos-norm",true);
 255     speedbrake_pos_pct
 256         =fgGetNode("/surface-positions/speedbrake-pos-norm",true);
 257     spoilers_pos_pct=fgGetNode("/surface-positions/spoilers-pos-norm",true);
 258     tailhook_pos_pct=fgGetNode("/gear/tailhook/position-norm",true);
 259     wing_fold_pos_pct=fgGetNode("surface-positions/wing-fold-pos-norm",true);
 260
 261     elevator_pos_pct->setDoubleValue(0);
 262     left_aileron_pos_pct->setDoubleValue(0);
 263     right_aileron_pos_pct->setDoubleValue(0);
 264     rudder_pos_pct->setDoubleValue(0);
 265     flap_pos_pct->setDoubleValue(0);
 266     speedbrake_pos_pct->setDoubleValue(0);
 267     spoilers_pos_pct->setDoubleValue(0);
 268
 269     ab_brake_engaged = fgGetNode("/autopilot/autobrake/engaged", true);
 270     ab_brake_left_pct = fgGetNode("/autopilot/autobrake/brake-left-output", true);
 271     ab_brake_right_pct = fgGetNode("/autopilot/autobrake/brake-right-output", true);
 272
 273     temperature = fgGetNode("/environment/temperature-degc",true);
 274     pressure = fgGetNode("/environment/pressure-inhg",true);
 275     density = fgGetNode("/environment/density-slugft3",true);
 276     turbulence_gain = fgGetNode("/environment/turbulence/magnitude-norm",true);
 277     turbulence_rate = fgGetNode("/environment/turbulence/rate-hz",true);
 278
 279     wind_from_north= fgGetNode("/environment/wind-from-north-fps",true);
 280     wind_from_east = fgGetNode("/environment/wind-from-east-fps" ,true);
 281     wind_from_down = fgGetNode("/environment/wind-from-down-fps" ,true);
 282
 283     slaved = fgGetNode("/sim/slaved/enabled", true);
 284
 285     for (unsigned int i = 0; i < Propulsion->GetNumEngines(); i++) {
 286       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 287       Propulsion->GetEngine(i)->GetThruster()->SetRPM(node->getDoubleValue("rpm") /
 288                      Propulsion->GetEngine(i)->GetThruster()->GetGearRatio());
 289     }
 290
 291     hook_root_struct = FGColumnVector3(
 292         fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-offset-x-in", 196),
 293         fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-offset-y-in", 0),
 294         fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-offset-z-in", -16));
 295     last_hook_tip[0] = 0; last_hook_tip[1] = 0; last_hook_tip[2] = 0;
 296     last_hook_root[0] = 0; last_hook_root[1] = 0; last_hook_root[2] = 0;
 297
 298     crashed = false;
 299 }
 300
 301 /******************************************************************************/
 302 FGJSBsim::~FGJSBsim(void)
 303 {
 304   delete fdmex;
 305 }
 306
 307 /******************************************************************************/
 308
 309 // Initialize the JSBsim flight model, dt is the time increment for
 310 // each subsequent iteration through the EOM
 311
 312 void FGJSBsim::init()
 313 {
 314     SG_LOG( SG_FLIGHT, SG_INFO, "Starting and initializing JSBsim" );
 315
 316     // Explicitly call the superclass's
 317     // init method first.
 318
 319     if (fgGetBool("/environment/params/control-fdm-atmosphere")) {
 320       Atmosphere->UseExternal();
 321       Atmosphere->SetExTemperature(
 322                   9.0/5.0*(temperature->getDoubleValue()+273.15) );
 323       Atmosphere->SetExPressure(pressure->getDoubleValue()*70.726566);
 324       Atmosphere->SetExDensity(density->getDoubleValue());
 325       Atmosphere->SetTurbType(FGAtmosphere::ttCulp);
 326       Atmosphere->SetTurbGain(turbulence_gain->getDoubleValue());
 327       Atmosphere->SetTurbRate(turbulence_rate->getDoubleValue());
 328
 329     } else {
 330       Atmosphere->UseInternal();
 331     }
 332
 333     fgic->SetVNorthFpsIC( -wind_from_north->getDoubleValue() );
 334     fgic->SetVEastFpsIC( -wind_from_east->getDoubleValue() );
 335     fgic->SetVDownFpsIC( -wind_from_down->getDoubleValue() );
 336
 337     //Atmosphere->SetExTemperature(get_Static_temperature());
 338     //Atmosphere->SetExPressure(get_Static_pressure());
 339     //Atmosphere->SetExDensity(get_Density());
 340     SG_LOG(SG_FLIGHT,SG_INFO,"T,p,rho: " << fdmex->GetAtmosphere()->GetTemperature()
 341      << ", " << fdmex->GetAtmosphere()->GetPressure()
 342      << ", " << fdmex->GetAtmosphere()->GetDensity() );
 343
 344 // deprecate egt_degf for egt-degf to have consistent naming
 345 // TODO: raise log-level to ALERT in summer 2010,
 346 // remove alias in fall 2010,
 347 // remove this code in winter 2010
 348     for (unsigned int i=0; i < Propulsion->GetNumEngines(); i++) {
 349       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 350       SGPropertyNode * egtn = node->getNode( "egt_degf" );
 351       if( egtn != NULL ) {
 352         SG_LOG(SG_FLIGHT,SG_WARN,
 353                "Aircraft uses deprecated node egt_degf. Please upgrade to egt-degf");
 354         node->getNode("egt-degf", true)->alias( egtn );
 355       }
 356     }
 357 // end of egt_degf deprecation patch
 358
 359     if (fgGetBool("/sim/presets/running")) {
 360           for (unsigned int i=0; i < Propulsion->GetNumEngines(); i++) {
 361             SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 362             node->setBoolValue("running", true);
 363             Propulsion->GetEngine(i)->SetRunning(true);
 364           }
 365     }
 366
 367     FCS->SetDfPos( ofNorm, globals->get_controls()->get_flaps() );
 368
 369     common_init();
 370
 371     copy_to_JSBsim();
 372     fdmex->RunIC();     //loop JSBSim once w/o integrating
 373     copy_from_JSBsim(); //update the bus
 374
 375     SG_LOG( SG_FLIGHT, SG_INFO, "  Initialized JSBSim with:" );
 376
 377     switch(fgic->GetSpeedSet()) {
 378     case setned:
 379         SG_LOG(SG_FLIGHT,SG_INFO, "  Vn,Ve,Vd= "
 380                << Propagate->GetVel(FGJSBBase::eNorth) << ", "
 381                << Propagate->GetVel(FGJSBBase::eEast) << ", "
 382                << Propagate->GetVel(FGJSBBase::eDown) << " ft/s");
 383     break;
 384     case setuvw:
 385         SG_LOG(SG_FLIGHT,SG_INFO, "  U,V,W= "
 386                << Propagate->GetUVW(1) << ", "
 387                << Propagate->GetUVW(2) << ", "
 388                << Propagate->GetUVW(3) << " ft/s");
 389     break;
 390     case setmach:
 391         SG_LOG(SG_FLIGHT,SG_INFO, "  Mach: "
 392                << Auxiliary->GetMach() );
 393     break;
 394     case setvc:
 395     default:
 396         SG_LOG(SG_FLIGHT,SG_INFO, "  Indicated Airspeed: "
 397                << Auxiliary->GetVcalibratedKTS() << " knots" );
 398     break;
 399     }
 400
 401     stall_warning->setDoubleValue(0);
 402
 403     SG_LOG( SG_FLIGHT, SG_INFO, "  Bank Angle: "
 404             << Propagate->GetEuler(FGJSBBase::ePhi)*RADTODEG << " deg" );
 405     SG_LOG( SG_FLIGHT, SG_INFO, "  Pitch Angle: "
 406             << Propagate->GetEuler(FGJSBBase::eTht)*RADTODEG << " deg" );
 407     SG_LOG( SG_FLIGHT, SG_INFO, "  True Heading: "
 408             << Propagate->GetEuler(FGJSBBase::ePsi)*RADTODEG << " deg" );
 409     SG_LOG( SG_FLIGHT, SG_INFO, "  Latitude: "
 410             << Propagate->GetLocation().GetLatitudeDeg() << " deg" );
 411     SG_LOG( SG_FLIGHT, SG_INFO, "  Longitude: "
 412             << Propagate->GetLocation().GetLongitudeDeg() << " deg" );
 413     SG_LOG( SG_FLIGHT, SG_INFO, "  Altitude: "
 414             << Propagate->GetAltitudeASL() << " feet" );
 415     SG_LOG( SG_FLIGHT, SG_INFO, "  loaded initial conditions" );
 416
 417     SG_LOG( SG_FLIGHT, SG_INFO, "  set dt" );
 418
 419     SG_LOG( SG_FLIGHT, SG_INFO, "Finished initializing JSBSim" );
 420
 421     SG_LOG( SG_FLIGHT, SG_INFO, "FGControls::get_gear_down()= " <<
 422                                   globals->get_controls()->get_gear_down() );
 423 }
 424
 425 /******************************************************************************/
 426
 427 void checkTied ( FGPropertyManager *node )
 428 {
 429   int N = node->nChildren();
 430   string name;
 431
 432   for (int i=0; i<N; i++) {
 433     if (node->getChild(i)->nChildren() ) {
 434       checkTied( (FGPropertyManager*)node->getChild(i) );
 435     }
 436     if ( node->getChild(i)->isTied() ) {
 437       name = ((FGPropertyManager*)node->getChild(i))->GetFullyQualifiedName();
 438       node->Untie(name);
 439     }
 440   }
 441 }
 442
 443 /******************************************************************************/
 444
 445 void FGJSBsim::unbind()
 446 {
 447   SGPropertyNode* instance = globals->get_props()->getNode("/fdm/jsbsim");
 448   checkTied((FGPropertyManager*)instance);
 449   FGInterface::unbind();
 450 }
 451
 452 /******************************************************************************/
 453
 454 // Run an iteration of the EOM (equations of motion)
 455
 456 void FGJSBsim::update( double dt )
 457 {
 458     if(crashed) {
 459       if(!fgGetBool("/sim/crashed"))
 460         fgSetBool("/sim/crashed", true);
 461       return;
 462     }
 463
 464     if (is_suspended())
 465       return;
 466
 467     int multiloop = _calc_multiloop(dt);
 468
 469     int i;
 470
 471     // Compute the radius of the aircraft. That is the radius of a ball
 472     // where all gear units are in. At the moment it is at least 10ft ...
 473     double acrad = 10.0;
 474     int n_gears = GroundReactions->GetNumGearUnits();
 475     for (i=0; i<n_gears; ++i) {
 476       FGColumnVector3 bl = GroundReactions->GetGearUnit(i)->GetBodyLocation();
 477       double r = bl.Magnitude();
 478       if (acrad < r)
 479         acrad = r;
 480     }
 481
 482     // Compute the potential movement of this aircraft and query for the
 483     // ground in this area.
 484     double groundCacheRadius = acrad + 2*dt*Propagate->GetUVW().Magnitude();
 485     double alt, slr, lat, lon;
 486     FGLocation cart = Auxiliary->GetLocationVRP();
 487     if ( needTrim && startup_trim->getBoolValue() ) {
 488       alt = fgic->GetAltitudeASLFtIC();
 489       slr = fgic->GetSeaLevelRadiusFtIC();
 490       lat = fgic->GetLatitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 491       lon = fgic->GetLongitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 492       cart = FGLocation(lon, lat, alt+slr);
 493     }
 494     double cart_pos[3] = { cart(1), cart(2), cart(3) };
 495     double t0 = fdmex->GetSimTime();
 496     bool cache_ok = prepare_ground_cache_ft( t0, t0 + dt, cart_pos,
 497                                              groundCacheRadius );
 498     if (!cache_ok) {
 499       SG_LOG(SG_FLIGHT, SG_WARN,
 500              "FGInterface is being called without scenery below the aircraft!");
 501
 502       alt = fgic->GetAltitudeASLFtIC();
 503       SG_LOG(SG_FLIGHT, SG_WARN, "altitude         = " << alt);
 504
 505       slr = fgic->GetSeaLevelRadiusFtIC();
 506       SG_LOG(SG_FLIGHT, SG_WARN, "sea level radius = " << slr);
 507
 508       lat = fgic->GetLatitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 509       SG_LOG(SG_FLIGHT, SG_WARN, "latitude         = " << lat);
 510
 511       lon = fgic->GetLongitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 512       SG_LOG(SG_FLIGHT, SG_WARN, "longitude        = " << lon);
 513       //return;
 514     }
 515
 516     copy_to_JSBsim();
 517
 518     trimmed->setBoolValue(false);
 519
 520     if ( needTrim ) {
 521       if ( startup_trim->getBoolValue() ) {
 522         double contact[3], d[3], vel[3], agl;
 523         get_agl_ft(fdmex->GetSimTime(), cart_pos, SG_METER_TO_FEET*2, contact,
 524                    d, vel, d, &agl);
 525         double terrain_alt = sqrt(contact[0]*contact[0] + contact[1]*contact[1]
 526              + contact[2]*contact[2]) - fgic->GetSeaLevelRadiusFtIC();
 527
 528         SG_LOG(SG_FLIGHT, SG_INFO,
 529           "Ready to trim, terrain elevation is: "
 530             << terrain_alt * SG_METER_TO_FEET );
 531
 532         if (fgGetBool("/sim/presets/onground")) {
 533           FGColumnVector3 gndVelNED = cart.GetTec2l()
 534                                     * FGColumnVector3(vel[0], vel[1], vel[2]);
 535           fgic->SetVNorthFpsIC(gndVelNED(1));
 536           fgic->SetVEastFpsIC(gndVelNED(2));
 537           fgic->SetVDownFpsIC(gndVelNED(3));
 538         }
 539         fgic->SetTerrainElevationFtIC( terrain_alt );
 540         do_trim();
 541       } else {
 542         fdmex->RunIC();  //apply any changes made through the set_ functions
 543       }
 544       needTrim = false;
 545     }
 546
 547     for ( i=0; i < multiloop; i++ ) {
 548       fdmex->Run();
 549       update_external_forces(fdmex->GetSimTime() + i * fdmex->GetDeltaT());
 550     }
 551
 552     FGJSBBase::Message* msg;
 553     while (msg = fdmex->ProcessNextMessage()) {
 554 //      msg = fdmex->ProcessNextMessage();
 555       switch (msg->type) {
 556       case FGJSBBase::Message::eText:
 557         if (msg->text == "Crash Detected: Simulation FREEZE.")
 558           crashed = true;
 559         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text );
 560         break;
 561       case FGJSBBase::Message::eBool:
 562         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->bVal );
 563         break;
 564       case FGJSBBase::Message::eInteger:
 565         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->iVal );
 566         break;
 567       case FGJSBBase::Message::eDouble:
 568         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->dVal );
 569         break;
 570       default:
 571         SG_LOG( SG_FLIGHT, SG_INFO, "Unrecognized message type." );
 572         break;
 573       }
 574     }
 575
 576     // translate JSBsim back to FG structure so that the
 577     // autopilot (and the rest of the sim can use the updated values
 578     copy_from_JSBsim();
 579 }
 580
 581 /******************************************************************************/
 582
 583 // Convert from the FGInterface struct to the JSBsim generic_ struct
 584
 585 bool FGJSBsim::copy_to_JSBsim()
 586 {
 587     double tmp;
 588     unsigned int i;
 589
 590     // copy control positions into the JSBsim structure
 591
 592     FCS->SetDaCmd( globals->get_controls()->get_aileron());
 593     FCS->SetRollTrimCmd( globals->get_controls()->get_aileron_trim() );
 594     FCS->SetDeCmd( globals->get_controls()->get_elevator());
 595     FCS->SetPitchTrimCmd( globals->get_controls()->get_elevator_trim() );
 596     FCS->SetDrCmd( -globals->get_controls()->get_rudder() );
 597     FCS->SetYawTrimCmd( -globals->get_controls()->get_rudder_trim() );
 598     FCS->SetDsCmd( globals->get_controls()->get_rudder() );
 599     FCS->SetDfCmd( globals->get_controls()->get_flaps() );
 600     FCS->SetDsbCmd( globals->get_controls()->get_speedbrake() );
 601     FCS->SetDspCmd( globals->get_controls()->get_spoilers() );
 602
 603         // Parking brake sets minimum braking
 604         // level for mains.
 605     double parking_brake = globals->get_controls()->get_brake_parking();
 606     double left_brake = globals->get_controls()->get_brake_left();
 607     double right_brake = globals->get_controls()->get_brake_right();
 608
 609     if (ab_brake_engaged->getBoolValue()) {
 610       left_brake = ab_brake_left_pct->getDoubleValue();
 611       right_brake = ab_brake_right_pct->getDoubleValue();
 612     }
 613
 614     FCS->SetLBrake(FMAX(left_brake, parking_brake));
 615     FCS->SetRBrake(FMAX(right_brake, parking_brake));
 616
 617
 618     FCS->SetCBrake( 0.0 );
 619     // FCS->SetCBrake( globals->get_controls()->get_brake(2) );
 620
 621     FCS->SetGearCmd( globals->get_controls()->get_gear_down());
 622     for (i = 0; i < Propulsion->GetNumEngines(); i++) {
 623       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 624
 625       FCS->SetThrottleCmd(i, globals->get_controls()->get_throttle(i));
 626       FCS->SetMixtureCmd(i, globals->get_controls()->get_mixture(i));
 627       FCS->SetPropAdvanceCmd(i, globals->get_controls()->get_prop_advance(i));
 628       FCS->SetFeatherCmd(i, globals->get_controls()->get_feather(i));
 629
 630       switch (Propulsion->GetEngine(i)->GetType()) {
 631       case FGEngine::etPiston:
 632         { // FGPiston code block
 633         FGPiston* eng = (FGPiston*)Propulsion->GetEngine(i);
 634         eng->SetMagnetos( globals->get_controls()->get_magnetos(i) );
 635         break;
 636         } // end FGPiston code block
 637       case FGEngine::etTurbine:
 638         { // FGTurbine code block
 639         FGTurbine* eng = (FGTurbine*)Propulsion->GetEngine(i);
 640         eng->SetAugmentation( globals->get_controls()->get_augmentation(i) );
 641         eng->SetReverse( globals->get_controls()->get_reverser(i) );
 642         //eng->SetInjection( globals->get_controls()->get_water_injection(i) );
 643         eng->SetCutoff( globals->get_controls()->get_cutoff(i) );
 644         eng->SetIgnition( globals->get_controls()->get_ignition(i) );
 645         break;
 646         } // end FGTurbine code block
 647       case FGEngine::etRocket:
 648         { // FGRocket code block
 649         FGRocket* eng = (FGRocket*)Propulsion->GetEngine(i);
 650         break;
 651         } // end FGRocket code block
 652       case FGEngine::etTurboprop:
 653         { // FGTurboProp code block
 654         FGTurboProp* eng = (FGTurboProp*)Propulsion->GetEngine(i);
 655         eng->SetReverse( globals->get_controls()->get_reverser(i) );
 656         eng->SetCutoff( globals->get_controls()->get_cutoff(i) );
 657         eng->SetIgnition( globals->get_controls()->get_ignition(i) );
 658
 659         eng->SetGeneratorPower( globals->get_controls()->get_generator_breaker(i) );
 660         eng->SetCondition( globals->get_controls()->get_condition(i) );
 661         break;
 662         } // end FGTurboProp code block
 663       default:
 664         break;
 665       }
 666
 667       { // FGEngine code block
 668       FGEngine* eng = Propulsion->GetEngine(i);
 669
 670       eng->SetStarter( globals->get_controls()->get_starter(i) );
 671       eng->SetRunning( node->getBoolValue("running") );
 672       } // end FGEngine code block
 673     }
 674
 675
 676     Propagate->SetSeaLevelRadius( get_Sea_level_radius() );
 677
 678     Atmosphere->SetExTemperature(
 679                   9.0/5.0*(temperature->getDoubleValue()+273.15) );
 680     Atmosphere->SetExPressure(pressure->getDoubleValue()*70.726566);
 681     Atmosphere->SetExDensity(density->getDoubleValue());
 682
 683     tmp = turbulence_gain->getDoubleValue();
 684     //Atmosphere->SetTurbGain(tmp * tmp * 100.0);
 685
 686     tmp = turbulence_rate->getDoubleValue();
 687     //Atmosphere->SetTurbRate(tmp);
 688
 689     Atmosphere->SetWindNED( -wind_from_north->getDoubleValue(),
 690                             -wind_from_east->getDoubleValue(),
 691                             -wind_from_down->getDoubleValue() );
 692 //    SG_LOG(SG_FLIGHT,SG_INFO, "Wind NED: "
 693 //                  << get_V_north_airmass() << ", "
 694 //                  << get_V_east_airmass()  << ", "
 695 //                  << get_V_down_airmass() );
 696
 697     for (i = 0; i < Propulsion->GetNumTanks(); i++) {
 698       SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
 699       FGTank * tank = Propulsion->GetTank(i);
 700       tank->SetContents(node->getDoubleValue("level-gal_us") * 6.6);
 701 //       tank->SetContents(node->getDoubleValue("level-lbs"));
 702     }
 703
 704     Propulsion->SetFuelFreeze((fgGetNode("/sim/freeze/fuel",true))->getBoolValue());
 705     fdmex->SetChild(slaved->getBoolValue());
 706
 707     return true;
 708 }
 709
 710 /******************************************************************************/
 711
 712 // Convert from the JSBsim generic_ struct to the FGInterface struct
 713
 714 bool FGJSBsim::copy_from_JSBsim()
 715 {
 716     unsigned int i, j;
 717 /*
 718     _set_Inertias( MassBalance->GetMass(),
 719                    MassBalance->GetIxx(),
 720                    MassBalance->GetIyy(),
 721                    MassBalance->GetIzz(),
 722                    MassBalance->GetIxz() );
 723 */
 724     _set_CG_Position( MassBalance->GetXYZcg(1),
 725                       MassBalance->GetXYZcg(2),
 726                       MassBalance->GetXYZcg(3) );
 727
 728     _set_Accels_Body( Aircraft->GetBodyAccel(1),
 729                       Aircraft->GetBodyAccel(2),
 730                       Aircraft->GetBodyAccel(3) );
 731
 732     _set_Accels_CG_Body_N ( Aircraft->GetNcg(1),
 733                             Aircraft->GetNcg(2),
 734                             Aircraft->GetNcg(3) );
 735
 736     _set_Accels_Pilot_Body( Auxiliary->GetPilotAccel(1),
 737                             Auxiliary->GetPilotAccel(2),
 738                             Auxiliary->GetPilotAccel(3) );
 739
 740     _set_Nlf( Aircraft->GetNlf() );
 741
 742     // Velocities
 743
 744     _set_Velocities_Local( Propagate->GetVel(FGJSBBase::eNorth),
 745                            Propagate->GetVel(FGJSBBase::eEast),
 746                            Propagate->GetVel(FGJSBBase::eDown) );
 747
 748     _set_Velocities_Wind_Body( Propagate->GetUVW(1),
 749                                Propagate->GetUVW(2),
 750                                Propagate->GetUVW(3) );
 751
 752     // Make the HUD work ...
 753     _set_Velocities_Ground( Propagate->GetVel(FGJSBBase::eNorth),
 754                             Propagate->GetVel(FGJSBBase::eEast),
 755                             -Propagate->GetVel(FGJSBBase::eDown) );
 756
 757     _set_V_rel_wind( Auxiliary->GetVt() );
 758
 759     _set_V_equiv_kts( Auxiliary->GetVequivalentKTS() );
 760
 761     _set_V_calibrated_kts( Auxiliary->GetVcalibratedKTS() );
 762
 763     _set_V_ground_speed( Auxiliary->GetVground() );
 764
 765     _set_Omega_Body( Propagate->GetPQR(FGJSBBase::eP),
 766                      Propagate->GetPQR(FGJSBBase::eQ),
 767                      Propagate->GetPQR(FGJSBBase::eR) );
 768
 769     _set_Euler_Rates( Auxiliary->GetEulerRates(FGJSBBase::ePhi),
 770                       Auxiliary->GetEulerRates(FGJSBBase::eTht),
 771                       Auxiliary->GetEulerRates(FGJSBBase::ePsi) );
 772
 773     _set_Mach_number( Auxiliary->GetMach() );
 774
 775     // Positions of Visual Reference Point
 776     FGLocation l = Auxiliary->GetLocationVRP();
 777     _updateGeocentricPosition( l.GetLatitude(), l.GetLongitude(),
 778                                l.GetRadius() - get_Sea_level_radius() );
 779
 780     _set_Altitude_AGL( Propagate->GetDistanceAGL() );
 781     {
 782       double loc_cart[3] = { l(FGJSBBase::eX), l(FGJSBBase::eY), l(FGJSBBase::eZ) };
 783       double contact[3], d[3], sd, t;
 784       is_valid_m(&t, d, &sd);
 785       get_agl_ft(t, loc_cart, SG_METER_TO_FEET*2, contact, d, d, d, &sd);
 786       double rwrad
 787         = FGColumnVector3( contact[0], contact[1], contact[2] ).Magnitude();
 788       _set_Runway_altitude( rwrad - get_Sea_level_radius() );
 789     }
 790
 791     _set_Euler_Angles( Propagate->GetEuler(FGJSBBase::ePhi),
 792                        Propagate->GetEuler(FGJSBBase::eTht),
 793                        Propagate->GetEuler(FGJSBBase::ePsi) );
 794
 795     _set_Alpha( Auxiliary->Getalpha() );
 796     _set_Beta( Auxiliary->Getbeta() );
 797
 798
 799     _set_Gamma_vert_rad( Auxiliary->GetGamma() );
 800
 801     _set_Earth_position_angle( Inertial->GetEarthPositionAngle() );
 802
 803     _set_Climb_Rate( Propagate->Gethdot() );
 804
 805     const FGMatrix33& Tl2b = Propagate->GetTl2b();
 806     for ( i = 1; i <= 3; i++ ) {
 807         for ( j = 1; j <= 3; j++ ) {
 808             _set_T_Local_to_Body( i, j, Tl2b(i,j) );
 809         }
 810     }
 811
 812     // Copy the engine values from JSBSim.
 813     for ( i=0; i < Propulsion->GetNumEngines(); i++ ) {
 814       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 815       SGPropertyNode * tnode = node->getChild("thruster", 0, true);
 816       FGThruster * thruster = Propulsion->GetEngine(i)->GetThruster();
 817
 818       switch (Propulsion->GetEngine(i)->GetType()) {
 819       case FGEngine::etPiston:
 820         { // FGPiston code block
 821         FGPiston* eng = (FGPiston*)Propulsion->GetEngine(i);
 822         node->setDoubleValue("egt-degf", eng->getExhaustGasTemp_degF());
 823         node->setDoubleValue("oil-temperature-degf", eng->getOilTemp_degF());
 824         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
 825         node->setDoubleValue("mp-osi", eng->getManifoldPressure_inHg());
 826         // NOTE: mp-osi is not in ounces per square inch.
 827         // This error is left for reasons of backwards compatibility with
 828         // existing FlightGear sound and instrument configurations.
 829         node->setDoubleValue("mp-inhg", eng->getManifoldPressure_inHg());
 830         node->setDoubleValue("cht-degf", eng->getCylinderHeadTemp_degF());
 831         node->setDoubleValue("rpm", eng->getRPM());
 832         } // end FGPiston code block
 833         break;
 834       case FGEngine::etRocket:
 835         { // FGRocket code block
 836         FGRocket* eng = (FGRocket*)Propulsion->GetEngine(i);
 837         } // end FGRocket code block
 838         break;
 839       case FGEngine::etTurbine:
 840         { // FGTurbine code block
 841         FGTurbine* eng = (FGTurbine*)Propulsion->GetEngine(i);
 842         node->setDoubleValue("n1", eng->GetN1());
 843         node->setDoubleValue("n2", eng->GetN2());
 844         node->setDoubleValue("egt-degf", 32 + eng->GetEGT()*9/5);
 845         node->setBoolValue("augmentation", eng->GetAugmentation());
 846         node->setBoolValue("water-injection", eng->GetInjection());
 847         node->setBoolValue("ignition", eng->GetIgnition());
 848         node->setDoubleValue("nozzle-pos-norm", eng->GetNozzle());
 849         node->setDoubleValue("inlet-pos-norm", eng->GetInlet());
 850         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
 851         node->setBoolValue("reversed", eng->GetReversed());
 852         node->setBoolValue("cutoff", eng->GetCutoff());
 853         node->setDoubleValue("epr", eng->GetEPR());
 854         globals->get_controls()->set_reverser(i, eng->GetReversed() );
 855         globals->get_controls()->set_cutoff(i, eng->GetCutoff() );
 856         globals->get_controls()->set_water_injection(i, eng->GetInjection() );
 857         globals->get_controls()->set_augmentation(i, eng->GetAugmentation() );
 858         } // end FGTurbine code block
 859         break;
 860       case FGEngine::etTurboprop:
 861         { // FGTurboProp code block
 862         FGTurboProp* eng = (FGTurboProp*)Propulsion->GetEngine(i);
 863         node->setDoubleValue("n1", eng->GetN1());
 864         //node->setDoubleValue("n2", eng->GetN2());
 865         node->setDoubleValue("itt_degf", 32 + eng->GetITT()*9/5);
 866         node->setBoolValue("ignition", eng->GetIgnition());
 867         node->setDoubleValue("nozzle-pos-norm", eng->GetNozzle());
 868         node->setDoubleValue("inlet-pos-norm", eng->GetInlet());
 869         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
 870         node->setBoolValue("reversed", eng->GetReversed());
 871         node->setBoolValue("cutoff", eng->GetCutoff());
 872         node->setBoolValue("starting", eng->GetEngStarting());
 873         node->setBoolValue("generator-power", eng->GetGeneratorPower());
 874         node->setBoolValue("damaged", eng->GetCondition());
 875         node->setBoolValue("ielu-intervent", eng->GetIeluIntervent());
 876         node->setDoubleValue("oil-temperature-degf", eng->getOilTemp_degF());
 877 //        node->setBoolValue("onfire", eng->GetFire());
 878         globals->get_controls()->set_reverser(i, eng->GetReversed() );
 879         globals->get_controls()->set_cutoff(i, eng->GetCutoff() );
 880         } // end FGTurboProp code block
 881         break;
 882       case FGEngine::etElectric:
 883         { // FGElectric code block
 884         FGElectric* eng = (FGElectric*)Propulsion->GetEngine(i);
 885         node->setDoubleValue("rpm", eng->getRPM());
 886         } // end FGElectric code block
 887         break;
 888       case FGEngine::etUnknown:
 889         break;
 890       }
 891
 892       { // FGEngine code block
 893       FGEngine* eng = Propulsion->GetEngine(i);
 894       node->setDoubleValue("fuel-flow-gph", eng->getFuelFlow_gph());
 895       node->setDoubleValue("thrust_lb", thruster->GetThrust());
 896       node->setDoubleValue("fuel-flow_pph", eng->getFuelFlow_pph());
 897       node->setBoolValue("running", eng->GetRunning());
 898       node->setBoolValue("starter", eng->GetStarter());
 899       node->setBoolValue("cranking", eng->GetCranking());
 900       globals->get_controls()->set_starter(i, eng->GetStarter() );
 901       } // end FGEngine code block
 902
 903       switch (thruster->GetType()) {
 904       case FGThruster::ttNozzle:
 905         { // FGNozzle code block
 906         FGNozzle* noz = (FGNozzle*)thruster;
 907         } // end FGNozzle code block
 908         break;
 909       case FGThruster::ttPropeller:
 910         { // FGPropeller code block
 911         FGPropeller* prop = (FGPropeller*)thruster;
 912         tnode->setDoubleValue("rpm", thruster->GetRPM());
 913         tnode->setDoubleValue("pitch", prop->GetPitch());
 914         tnode->setDoubleValue("torque", prop->GetTorque());
 915         tnode->setBoolValue("feathered", prop->GetFeather());
 916         } // end FGPropeller code block
 917         break;
 918       case FGThruster::ttRotor:
 919         { // FGRotor code block
 920         FGRotor* rotor = (FGRotor*)thruster;
 921         } // end FGRotor code block
 922         break;
 923       case FGThruster::ttDirect:
 924         { // Direct code block
 925         } // end Direct code block
 926         break;
 927       }
 928
 929     }
 930
 931     // Copy the fuel levels from JSBSim if fuel
 932     // freeze not enabled.
 933     if ( ! Propulsion->GetFuelFreeze() ) {
 934       for (i = 0; i < Propulsion->GetNumTanks(); i++) {
 935         SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
 936         FGTank* tank = Propulsion->GetTank(i);
 937         double contents = tank->GetContents();
 938         double temp = tank->GetTemperature_degC();
 939         node->setDoubleValue("level-gal_us", contents/6.6);
 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
1445
1446 void FGJSBsim::resetPropertyState()
1447 {
1448 // this code works-around bug #222:
1449 // http://code.google.com/p/flightgear-bugs/issues/detail?id=222
1450 // for whatever reason, having an existing value for the WOW
1451 // property causes the NaNs. Should that be fixed, this code can die
1452   SGPropertyNode* gear = fgGetNode("/fdm/jsbsim/gear", false);
1453   if (!gear) {
1454     return;
1455   }
1456
1457   int index = 0;
1458   SGPropertyNode* unitNode = NULL;
1459   for (; (unitNode = gear->getChild("unit", index)) != NULL; ++index) {
1460     unitNode->removeChild("WOW", 0, false);
1461   }
1462 }
1463