src/FDM/JSBSim/JSBSim.cxx

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