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 // Run an iteration of the EOM (equations of motion)
 428
 429 void FGJSBsim::update( double dt )
 430 {
 431     if(crashed) {
 432       if(!fgGetBool("/sim/crashed"))
 433         fgSetBool("/sim/crashed", true);
 434       return;
 435     }
 436
 437     if (is_suspended())
 438       return;
 439
 440     int multiloop = _calc_multiloop(dt);
 441
 442     int i;
 443
 444     // Compute the radius of the aircraft. That is the radius of a ball
 445     // where all gear units are in. At the moment it is at least 10ft ...
 446     double acrad = 10.0;
 447     int n_gears = GroundReactions->GetNumGearUnits();
 448     for (i=0; i<n_gears; ++i) {
 449       FGColumnVector3 bl = GroundReactions->GetGearUnit(i)->GetBodyLocation();
 450       double r = bl.Magnitude();
 451       if (acrad < r)
 452         acrad = r;
 453     }
 454
 455     // Compute the potential movement of this aircraft and query for the
 456     // ground in this area.
 457     double groundCacheRadius = acrad + 2*dt*Propagate->GetUVW().Magnitude();
 458     double alt, slr, lat, lon;
 459     FGLocation cart = Auxiliary->GetLocationVRP();
 460     if ( needTrim && startup_trim->getBoolValue() ) {
 461       alt = fgic->GetAltitudeASLFtIC();
 462       slr = fgic->GetSeaLevelRadiusFtIC();
 463       lat = fgic->GetLatitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 464       lon = fgic->GetLongitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 465       cart = FGLocation(lon, lat, alt+slr);
 466     }
 467     double cart_pos[3] = { cart(1), cart(2), cart(3) };
 468     double t0 = fdmex->GetSimTime();
 469     bool cache_ok = prepare_ground_cache_ft( t0, t0 + dt, cart_pos,
 470                                              groundCacheRadius );
 471     if (!cache_ok) {
 472       SG_LOG(SG_FLIGHT, SG_WARN,
 473              "FGInterface is being called without scenery below the aircraft!");
 474
 475       alt = fgic->GetAltitudeASLFtIC();
 476       SG_LOG(SG_FLIGHT, SG_WARN, "altitude         = " << alt);
 477
 478       slr = fgic->GetSeaLevelRadiusFtIC();
 479       SG_LOG(SG_FLIGHT, SG_WARN, "sea level radius = " << slr);
 480
 481       lat = fgic->GetLatitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 482       SG_LOG(SG_FLIGHT, SG_WARN, "latitude         = " << lat);
 483
 484       lon = fgic->GetLongitudeDegIC() * SGD_DEGREES_TO_RADIANS;
 485       SG_LOG(SG_FLIGHT, SG_WARN, "longitude        = " << lon);
 486       //return;
 487     }
 488
 489     copy_to_JSBsim();
 490
 491     trimmed->setBoolValue(false);
 492
 493     if ( needTrim ) {
 494       if ( startup_trim->getBoolValue() ) {
 495         double contact[3], d[3], vel[3], agl;
 496         get_agl_ft(fdmex->GetSimTime(), cart_pos, SG_METER_TO_FEET*2, contact,
 497                    d, vel, d, &agl);
 498         double terrain_alt = sqrt(contact[0]*contact[0] + contact[1]*contact[1]
 499              + contact[2]*contact[2]) - fgic->GetSeaLevelRadiusFtIC();
 500
 501         SG_LOG(SG_FLIGHT, SG_INFO,
 502           "Ready to trim, terrain elevation is: "
 503             << terrain_alt * SG_METER_TO_FEET );
 504
 505         if (fgGetBool("/sim/presets/onground")) {
 506           FGColumnVector3 gndVelNED = cart.GetTec2l()
 507                                     * FGColumnVector3(vel[0], vel[1], vel[2]);
 508           fgic->SetVNorthFpsIC(gndVelNED(1));
 509           fgic->SetVEastFpsIC(gndVelNED(2));
 510           fgic->SetVDownFpsIC(gndVelNED(3));
 511         }
 512         fgic->SetTerrainElevationFtIC( terrain_alt );
 513         do_trim();
 514       } else {
 515         fdmex->RunIC();  //apply any changes made through the set_ functions
 516       }
 517       needTrim = false;
 518     }
 519
 520     for ( i=0; i < multiloop; i++ ) {
 521       fdmex->Run();
 522       update_external_forces(fdmex->GetSimTime() + i * fdmex->GetDeltaT());
 523     }
 524
 525     FGJSBBase::Message* msg;
 526     while (msg = fdmex->ProcessNextMessage()) {
 527 //      msg = fdmex->ProcessNextMessage();
 528       switch (msg->type) {
 529       case FGJSBBase::Message::eText:
 530         if (msg->text == "Crash Detected: Simulation FREEZE.")
 531           crashed = true;
 532         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text );
 533         break;
 534       case FGJSBBase::Message::eBool:
 535         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->bVal );
 536         break;
 537       case FGJSBBase::Message::eInteger:
 538         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->iVal );
 539         break;
 540       case FGJSBBase::Message::eDouble:
 541         SG_LOG( SG_FLIGHT, SG_INFO, msg->messageId << ": " << msg->text << " " << msg->dVal );
 542         break;
 543       default:
 544         SG_LOG( SG_FLIGHT, SG_INFO, "Unrecognized message type." );
 545         break;
 546       }
 547     }
 548
 549     // translate JSBsim back to FG structure so that the
 550     // autopilot (and the rest of the sim can use the updated values
 551     copy_from_JSBsim();
 552 }
 553
 554 /******************************************************************************/
 555
 556 // Convert from the FGInterface struct to the JSBsim generic_ struct
 557
 558 bool FGJSBsim::copy_to_JSBsim()
 559 {
 560     double tmp;
 561     unsigned int i;
 562
 563     // copy control positions into the JSBsim structure
 564
 565     FCS->SetDaCmd( globals->get_controls()->get_aileron());
 566     FCS->SetRollTrimCmd( globals->get_controls()->get_aileron_trim() );
 567     FCS->SetDeCmd( globals->get_controls()->get_elevator());
 568     FCS->SetPitchTrimCmd( globals->get_controls()->get_elevator_trim() );
 569     FCS->SetDrCmd( -globals->get_controls()->get_rudder() );
 570     FCS->SetYawTrimCmd( -globals->get_controls()->get_rudder_trim() );
 571     FCS->SetDsCmd( globals->get_controls()->get_rudder() );
 572     FCS->SetDfCmd( globals->get_controls()->get_flaps() );
 573     FCS->SetDsbCmd( globals->get_controls()->get_speedbrake() );
 574     FCS->SetDspCmd( globals->get_controls()->get_spoilers() );
 575
 576         // Parking brake sets minimum braking
 577         // level for mains.
 578     double parking_brake = globals->get_controls()->get_brake_parking();
 579     double left_brake = globals->get_controls()->get_brake_left();
 580     double right_brake = globals->get_controls()->get_brake_right();
 581
 582     if (ab_brake_engaged->getBoolValue()) {
 583       left_brake = ab_brake_left_pct->getDoubleValue();
 584       right_brake = ab_brake_right_pct->getDoubleValue();
 585     }
 586
 587     FCS->SetLBrake(FMAX(left_brake, parking_brake));
 588     FCS->SetRBrake(FMAX(right_brake, parking_brake));
 589
 590
 591     FCS->SetCBrake( 0.0 );
 592     // FCS->SetCBrake( globals->get_controls()->get_brake(2) );
 593
 594     FCS->SetGearCmd( globals->get_controls()->get_gear_down());
 595     for (i = 0; i < Propulsion->GetNumEngines(); i++) {
 596       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 597
 598       FCS->SetThrottleCmd(i, globals->get_controls()->get_throttle(i));
 599       FCS->SetMixtureCmd(i, globals->get_controls()->get_mixture(i));
 600       FCS->SetPropAdvanceCmd(i, globals->get_controls()->get_prop_advance(i));
 601       FCS->SetFeatherCmd(i, globals->get_controls()->get_feather(i));
 602
 603       switch (Propulsion->GetEngine(i)->GetType()) {
 604       case FGEngine::etPiston:
 605         { // FGPiston code block
 606         FGPiston* eng = (FGPiston*)Propulsion->GetEngine(i);
 607         eng->SetMagnetos( globals->get_controls()->get_magnetos(i) );
 608         break;
 609         } // end FGPiston code block
 610       case FGEngine::etTurbine:
 611         { // FGTurbine code block
 612         FGTurbine* eng = (FGTurbine*)Propulsion->GetEngine(i);
 613         eng->SetAugmentation( globals->get_controls()->get_augmentation(i) );
 614         eng->SetReverse( globals->get_controls()->get_reverser(i) );
 615         //eng->SetInjection( globals->get_controls()->get_water_injection(i) );
 616         eng->SetCutoff( globals->get_controls()->get_cutoff(i) );
 617         eng->SetIgnition( globals->get_controls()->get_ignition(i) );
 618         break;
 619         } // end FGTurbine code block
 620       case FGEngine::etRocket:
 621         { // FGRocket code block
 622         FGRocket* eng = (FGRocket*)Propulsion->GetEngine(i);
 623         break;
 624         } // end FGRocket code block
 625       case FGEngine::etTurboprop:
 626         { // FGTurboProp code block
 627         FGTurboProp* eng = (FGTurboProp*)Propulsion->GetEngine(i);
 628         eng->SetReverse( globals->get_controls()->get_reverser(i) );
 629         eng->SetCutoff( globals->get_controls()->get_cutoff(i) );
 630         eng->SetIgnition( globals->get_controls()->get_ignition(i) );
 631
 632         eng->SetGeneratorPower( globals->get_controls()->get_generator_breaker(i) );
 633         eng->SetCondition( globals->get_controls()->get_condition(i) );
 634         break;
 635         } // end FGTurboProp code block
 636       default:
 637         break;
 638       }
 639
 640       { // FGEngine code block
 641       FGEngine* eng = Propulsion->GetEngine(i);
 642
 643       eng->SetStarter( globals->get_controls()->get_starter(i) );
 644       eng->SetRunning( node->getBoolValue("running") );
 645       } // end FGEngine code block
 646     }
 647
 648
 649     Propagate->SetSeaLevelRadius( get_Sea_level_radius() );
 650
 651     Atmosphere->SetExTemperature(
 652                   9.0/5.0*(temperature->getDoubleValue()+273.15) );
 653     Atmosphere->SetExPressure(pressure->getDoubleValue()*70.726566);
 654     Atmosphere->SetExDensity(density->getDoubleValue());
 655
 656     tmp = turbulence_gain->getDoubleValue();
 657     //Atmosphere->SetTurbGain(tmp * tmp * 100.0);
 658
 659     tmp = turbulence_rate->getDoubleValue();
 660     //Atmosphere->SetTurbRate(tmp);
 661
 662     Atmosphere->SetWindNED( -wind_from_north->getDoubleValue(),
 663                             -wind_from_east->getDoubleValue(),
 664                             -wind_from_down->getDoubleValue() );
 665 //    SG_LOG(SG_FLIGHT,SG_INFO, "Wind NED: "
 666 //                  << get_V_north_airmass() << ", "
 667 //                  << get_V_east_airmass()  << ", "
 668 //                  << get_V_down_airmass() );
 669
 670     for (i = 0; i < Propulsion->GetNumTanks(); i++) {
 671       SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
 672       FGTank * tank = Propulsion->GetTank(i);
 673       tank->SetContents(node->getDoubleValue("level-gal_us") * 6.6);
 674 //       tank->SetContents(node->getDoubleValue("level-lbs"));
 675     }
 676
 677     Propulsion->SetFuelFreeze((fgGetNode("/sim/freeze/fuel",true))->getBoolValue());
 678     fdmex->SetChild(slaved->getBoolValue());
 679
 680     return true;
 681 }
 682
 683 /******************************************************************************/
 684
 685 // Convert from the JSBsim generic_ struct to the FGInterface struct
 686
 687 bool FGJSBsim::copy_from_JSBsim()
 688 {
 689     unsigned int i, j;
 690 /*
 691     _set_Inertias( MassBalance->GetMass(),
 692                    MassBalance->GetIxx(),
 693                    MassBalance->GetIyy(),
 694                    MassBalance->GetIzz(),
 695                    MassBalance->GetIxz() );
 696 */
 697     _set_CG_Position( MassBalance->GetXYZcg(1),
 698                       MassBalance->GetXYZcg(2),
 699                       MassBalance->GetXYZcg(3) );
 700
 701     _set_Accels_Body( Aircraft->GetBodyAccel(1),
 702                       Aircraft->GetBodyAccel(2),
 703                       Aircraft->GetBodyAccel(3) );
 704
 705     _set_Accels_CG_Body_N ( Aircraft->GetNcg(1),
 706                             Aircraft->GetNcg(2),
 707                             Aircraft->GetNcg(3) );
 708
 709     _set_Accels_Pilot_Body( Auxiliary->GetPilotAccel(1),
 710                             Auxiliary->GetPilotAccel(2),
 711                             Auxiliary->GetPilotAccel(3) );
 712
 713     _set_Nlf( Aircraft->GetNlf() );
 714
 715     // Velocities
 716
 717     _set_Velocities_Local( Propagate->GetVel(FGJSBBase::eNorth),
 718                            Propagate->GetVel(FGJSBBase::eEast),
 719                            Propagate->GetVel(FGJSBBase::eDown) );
 720
 721     _set_Velocities_Wind_Body( Propagate->GetUVW(1),
 722                                Propagate->GetUVW(2),
 723                                Propagate->GetUVW(3) );
 724
 725     // Make the HUD work ...
 726     _set_Velocities_Ground( Propagate->GetVel(FGJSBBase::eNorth),
 727                             Propagate->GetVel(FGJSBBase::eEast),
 728                             -Propagate->GetVel(FGJSBBase::eDown) );
 729
 730     _set_V_rel_wind( Auxiliary->GetVt() );
 731
 732     _set_V_equiv_kts( Auxiliary->GetVequivalentKTS() );
 733
 734     _set_V_calibrated_kts( Auxiliary->GetVcalibratedKTS() );
 735
 736     _set_V_ground_speed( Auxiliary->GetVground() );
 737
 738     _set_Omega_Body( Propagate->GetPQR(FGJSBBase::eP),
 739                      Propagate->GetPQR(FGJSBBase::eQ),
 740                      Propagate->GetPQR(FGJSBBase::eR) );
 741
 742     _set_Euler_Rates( Auxiliary->GetEulerRates(FGJSBBase::ePhi),
 743                       Auxiliary->GetEulerRates(FGJSBBase::eTht),
 744                       Auxiliary->GetEulerRates(FGJSBBase::ePsi) );
 745
 746     _set_Mach_number( Auxiliary->GetMach() );
 747
 748     // Positions of Visual Reference Point
 749     FGLocation l = Auxiliary->GetLocationVRP();
 750     _updateGeocentricPosition( l.GetLatitude(), l.GetLongitude(),
 751                                l.GetRadius() - get_Sea_level_radius() );
 752
 753     _set_Altitude_AGL( Propagate->GetDistanceAGL() );
 754     {
 755       double loc_cart[3] = { l(FGJSBBase::eX), l(FGJSBBase::eY), l(FGJSBBase::eZ) };
 756       double contact[3], d[3], sd, t;
 757       is_valid_m(&t, d, &sd);
 758       get_agl_ft(t, loc_cart, SG_METER_TO_FEET*2, contact, d, d, d, &sd);
 759       double rwrad
 760         = FGColumnVector3( contact[0], contact[1], contact[2] ).Magnitude();
 761       _set_Runway_altitude( rwrad - get_Sea_level_radius() );
 762     }
 763
 764     _set_Euler_Angles( Propagate->GetEuler(FGJSBBase::ePhi),
 765                        Propagate->GetEuler(FGJSBBase::eTht),
 766                        Propagate->GetEuler(FGJSBBase::ePsi) );
 767
 768     _set_Alpha( Auxiliary->Getalpha() );
 769     _set_Beta( Auxiliary->Getbeta() );
 770
 771
 772     _set_Gamma_vert_rad( Auxiliary->GetGamma() );
 773
 774     _set_Earth_position_angle( Inertial->GetEarthPositionAngle() );
 775
 776     _set_Climb_Rate( Propagate->Gethdot() );
 777
 778     const FGMatrix33& Tl2b = Propagate->GetTl2b();
 779     for ( i = 1; i <= 3; i++ ) {
 780         for ( j = 1; j <= 3; j++ ) {
 781             _set_T_Local_to_Body( i, j, Tl2b(i,j) );
 782         }
 783     }
 784
 785     // Copy the engine values from JSBSim.
 786     for ( i=0; i < Propulsion->GetNumEngines(); i++ ) {
 787       SGPropertyNode * node = fgGetNode("engines/engine", i, true);
 788       SGPropertyNode * tnode = node->getChild("thruster", 0, true);
 789       FGThruster * thruster = Propulsion->GetEngine(i)->GetThruster();
 790
 791       switch (Propulsion->GetEngine(i)->GetType()) {
 792       case FGEngine::etPiston:
 793         { // FGPiston code block
 794         FGPiston* eng = (FGPiston*)Propulsion->GetEngine(i);
 795         node->setDoubleValue("egt-degf", eng->getExhaustGasTemp_degF());
 796         node->setDoubleValue("oil-temperature-degf", eng->getOilTemp_degF());
 797         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
 798         node->setDoubleValue("mp-osi", eng->getManifoldPressure_inHg());
 799         // NOTE: mp-osi is not in ounces per square inch.
 800         // This error is left for reasons of backwards compatibility with
 801         // existing FlightGear sound and instrument configurations.
 802         node->setDoubleValue("mp-inhg", eng->getManifoldPressure_inHg());
 803         node->setDoubleValue("cht-degf", eng->getCylinderHeadTemp_degF());
 804         node->setDoubleValue("rpm", eng->getRPM());
 805         } // end FGPiston code block
 806         break;
 807       case FGEngine::etRocket:
 808         { // FGRocket code block
 809         FGRocket* eng = (FGRocket*)Propulsion->GetEngine(i);
 810         } // end FGRocket code block
 811         break;
 812       case FGEngine::etTurbine:
 813         { // FGTurbine code block
 814         FGTurbine* eng = (FGTurbine*)Propulsion->GetEngine(i);
 815         node->setDoubleValue("n1", eng->GetN1());
 816         node->setDoubleValue("n2", eng->GetN2());
 817         node->setDoubleValue("egt-degf", 32 + eng->GetEGT()*9/5);
 818         node->setBoolValue("augmentation", eng->GetAugmentation());
 819         node->setBoolValue("water-injection", eng->GetInjection());
 820         node->setBoolValue("ignition", eng->GetIgnition());
 821         node->setDoubleValue("nozzle-pos-norm", eng->GetNozzle());
 822         node->setDoubleValue("inlet-pos-norm", eng->GetInlet());
 823         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
 824         node->setBoolValue("reversed", eng->GetReversed());
 825         node->setBoolValue("cutoff", eng->GetCutoff());
 826         node->setDoubleValue("epr", eng->GetEPR());
 827         globals->get_controls()->set_reverser(i, eng->GetReversed() );
 828         globals->get_controls()->set_cutoff(i, eng->GetCutoff() );
 829         globals->get_controls()->set_water_injection(i, eng->GetInjection() );
 830         globals->get_controls()->set_augmentation(i, eng->GetAugmentation() );
 831         } // end FGTurbine code block
 832         break;
 833       case FGEngine::etTurboprop:
 834         { // FGTurboProp code block
 835         FGTurboProp* eng = (FGTurboProp*)Propulsion->GetEngine(i);
 836         node->setDoubleValue("n1", eng->GetN1());
 837         //node->setDoubleValue("n2", eng->GetN2());
 838         node->setDoubleValue("itt_degf", 32 + eng->GetITT()*9/5);
 839         node->setBoolValue("ignition", eng->GetIgnition());
 840         node->setDoubleValue("nozzle-pos-norm", eng->GetNozzle());
 841         node->setDoubleValue("inlet-pos-norm", eng->GetInlet());
 842         node->setDoubleValue("oil-pressure-psi", eng->getOilPressure_psi());
 843         node->setBoolValue("reversed", eng->GetReversed());
 844         node->setBoolValue("cutoff", eng->GetCutoff());
 845         node->setBoolValue("starting", eng->GetEngStarting());
 846         node->setBoolValue("generator-power", eng->GetGeneratorPower());
 847         node->setBoolValue("damaged", eng->GetCondition());
 848         node->setBoolValue("ielu-intervent", eng->GetIeluIntervent());
 849         node->setDoubleValue("oil-temperature-degf", eng->getOilTemp_degF());
 850 //        node->setBoolValue("onfire", eng->GetFire());
 851         globals->get_controls()->set_reverser(i, eng->GetReversed() );
 852         globals->get_controls()->set_cutoff(i, eng->GetCutoff() );
 853         } // end FGTurboProp code block
 854         break;
 855       case FGEngine::etElectric:
 856         { // FGElectric code block
 857         FGElectric* eng = (FGElectric*)Propulsion->GetEngine(i);
 858         node->setDoubleValue("rpm", eng->getRPM());
 859         } // end FGElectric code block
 860         break;
 861       case FGEngine::etUnknown:
 862         break;
 863       }
 864
 865       { // FGEngine code block
 866       FGEngine* eng = Propulsion->GetEngine(i);
 867       node->setDoubleValue("fuel-flow-gph", eng->getFuelFlow_gph());
 868       node->setDoubleValue("thrust_lb", thruster->GetThrust());
 869       node->setDoubleValue("fuel-flow_pph", eng->getFuelFlow_pph());
 870       node->setBoolValue("running", eng->GetRunning());
 871       node->setBoolValue("starter", eng->GetStarter());
 872       node->setBoolValue("cranking", eng->GetCranking());
 873       globals->get_controls()->set_starter(i, eng->GetStarter() );
 874       } // end FGEngine code block
 875
 876       switch (thruster->GetType()) {
 877       case FGThruster::ttNozzle:
 878         { // FGNozzle code block
 879         FGNozzle* noz = (FGNozzle*)thruster;
 880         } // end FGNozzle code block
 881         break;
 882       case FGThruster::ttPropeller:
 883         { // FGPropeller code block
 884         FGPropeller* prop = (FGPropeller*)thruster;
 885         tnode->setDoubleValue("rpm", thruster->GetRPM());
 886         tnode->setDoubleValue("pitch", prop->GetPitch());
 887         tnode->setDoubleValue("torque", prop->GetTorque());
 888         tnode->setBoolValue("feathered", prop->GetFeather());
 889         } // end FGPropeller code block
 890         break;
 891       case FGThruster::ttRotor:
 892         { // FGRotor code block
 893         FGRotor* rotor = (FGRotor*)thruster;
 894         } // end FGRotor code block
 895         break;
 896       case FGThruster::ttDirect:
 897         { // Direct code block
 898         } // end Direct code block
 899         break;
 900       }
 901
 902     }
 903
 904     // Copy the fuel levels from JSBSim if fuel
 905     // freeze not enabled.
 906     if ( ! Propulsion->GetFuelFreeze() ) {
 907       for (i = 0; i < Propulsion->GetNumTanks(); i++) {
 908         SGPropertyNode * node = fgGetNode("/consumables/fuel/tank", i, true);
 909         FGTank* tank = Propulsion->GetTank(i);
 910         double contents = tank->GetContents();
 911         double temp = tank->GetTemperature_degC();
 912         node->setDoubleValue("level-gal_us", contents/6.6);
 913         node->setDoubleValue("level-lbs", contents);
 914         if (temp != -9999.0) node->setDoubleValue("temperature_degC", temp);
 915       }
 916     }
 917
 918     update_gear();
 919
 920     stall_warning->setDoubleValue( Aerodynamics->GetStallWarn() );
 921
 922     elevator_pos_pct->setDoubleValue( FCS->GetDePos(ofNorm) );
 923     left_aileron_pos_pct->setDoubleValue( FCS->GetDaLPos(ofNorm) );
 924     right_aileron_pos_pct->setDoubleValue( FCS->GetDaRPos(ofNorm) );
 925     rudder_pos_pct->setDoubleValue( -1*FCS->GetDrPos(ofNorm) );
 926     flap_pos_pct->setDoubleValue( FCS->GetDfPos(ofNorm) );
 927     speedbrake_pos_pct->setDoubleValue( FCS->GetDsbPos(ofNorm) );
 928     spoilers_pos_pct->setDoubleValue( FCS->GetDspPos(ofNorm) );
 929     tailhook_pos_pct->setDoubleValue( FCS->GetTailhookPos() );
 930     wing_fold_pos_pct->setDoubleValue( FCS->GetWingFoldPos() );
 931
 932     // force a sim crashed if crashed (altitude AGL < 0)
 933     if (get_Altitude_AGL() < -100.0) {
 934          fdmex->SuspendIntegration();
 935          crashed = true;
 936     }
 937
 938     return true;
 939 }
 940
 941
 942 bool FGJSBsim::ToggleDataLogging(void)
 943 {
 944   // ToDo: handle this properly
 945   fdmex->DisableOutput();
 946   return false;
 947 }
 948
 949
 950 bool FGJSBsim::ToggleDataLogging(bool state)
 951 {
 952     if (state) {
 953       fdmex->EnableOutput();
 954       return true;
 955     } else {
 956       fdmex->DisableOutput();
 957       return false;
 958     }
 959 }
 960
 961
 962 //Positions
 963 void FGJSBsim::set_Latitude(double lat)
 964 {
 965     static SGConstPropertyNode_ptr altitude = fgGetNode("/position/altitude-ft");
 966     double alt;
 967     double sea_level_radius_meters, lat_geoc;
 968
 969     // In case we're not trimming
 970     FGInterface::set_Latitude(lat);
 971
 972     if ( altitude->getDoubleValue() > -9990 ) {
 973       alt = altitude->getDoubleValue();
 974     } else {
 975       alt = 0.0;
 976     }
 977
 978     update_ic();
 979     SG_LOG(SG_FLIGHT,SG_INFO,"FGJSBsim::set_Latitude: " << lat );
 980     SG_LOG(SG_FLIGHT,SG_INFO," cur alt (ft) =  " << alt );
 981
 982     sgGeodToGeoc( lat, alt * SG_FEET_TO_METER,
 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     fgic->SetLatitudeRadIC( lat_geoc );
 987     needTrim=true;
 988 }
 989
 990
 991 void FGJSBsim::set_Longitude(double lon)
 992 {
 993     SG_LOG(SG_FLIGHT,SG_INFO,"FGJSBsim::set_Longitude: " << lon );
 994
 995     // In case we're not trimming
 996     FGInterface::set_Longitude(lon);
 997
 998     update_ic();
 999     fgic->SetLongitudeRadIC( lon );
1000     needTrim=true;
1001 }
1002
1003 // Sets the altitude above sea level.
1004 void FGJSBsim::set_Altitude(double alt)
1005 {
1006     static SGConstPropertyNode_ptr latitude = fgGetNode("/position/latitude-deg");
1007
1008     double sea_level_radius_meters,lat_geoc;
1009
1010     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Altitude: " << alt );
1011     SG_LOG(SG_FLIGHT,SG_INFO, "  lat (deg) = " << latitude->getDoubleValue() );
1012
1013     // In case we're not trimming
1014     FGInterface::set_Altitude(alt);
1015
1016     update_ic();
1017     sgGeodToGeoc( latitude->getDoubleValue() * SGD_DEGREES_TO_RADIANS, alt,
1018                   &sea_level_radius_meters, &lat_geoc);
1019     _set_Sea_level_radius( sea_level_radius_meters * SG_METER_TO_FEET  );
1020     fgic->SetSeaLevelRadiusFtIC( sea_level_radius_meters * SG_METER_TO_FEET );
1021     SG_LOG(SG_FLIGHT, SG_INFO,
1022           "Terrain elevation: " << FGInterface::get_Runway_altitude() * SG_METER_TO_FEET );
1023     fgic->SetLatitudeRadIC( lat_geoc );
1024     fgic->SetAltitudeASLFtIC(alt);
1025     needTrim=true;
1026 }
1027
1028 void FGJSBsim::set_V_calibrated_kts(double vc)
1029 {
1030     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_V_calibrated_kts: " <<  vc );
1031
1032     // In case we're not trimming
1033     FGInterface::set_V_calibrated_kts(vc);
1034
1035     update_ic();
1036     fgic->SetVcalibratedKtsIC(vc);
1037     needTrim=true;
1038 }
1039
1040 void FGJSBsim::set_Mach_number(double mach)
1041 {
1042     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Mach_number: " <<  mach );
1043
1044     // In case we're not trimming
1045     FGInterface::set_Mach_number(mach);
1046
1047     update_ic();
1048     fgic->SetMachIC(mach);
1049     needTrim=true;
1050 }
1051
1052 void FGJSBsim::set_Velocities_Local( double north, double east, double down )
1053 {
1054     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Velocities_Local: "
1055        << north << ", " <<  east << ", " << down );
1056
1057     // In case we're not trimming
1058     FGInterface::set_Velocities_Local(north, east, down);
1059
1060     update_ic();
1061     fgic->SetVNorthFpsIC(north);
1062     fgic->SetVEastFpsIC(east);
1063     fgic->SetVDownFpsIC(down);
1064     needTrim=true;
1065 }
1066
1067 void FGJSBsim::set_Velocities_Wind_Body( double u, double v, double w)
1068 {
1069     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Velocities_Wind_Body: "
1070        << u << ", " <<  v << ", " <<  w );
1071
1072     // In case we're not trimming
1073     FGInterface::set_Velocities_Wind_Body(u, v, w);
1074
1075     update_ic();
1076     fgic->SetUBodyFpsIC(u);
1077     fgic->SetVBodyFpsIC(v);
1078     fgic->SetWBodyFpsIC(w);
1079     needTrim=true;
1080 }
1081
1082 //Euler angles
1083 void FGJSBsim::set_Euler_Angles( double phi, double theta, double psi )
1084 {
1085     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Euler_Angles: "
1086        << phi << ", " << theta << ", " << psi );
1087
1088     // In case we're not trimming
1089     FGInterface::set_Euler_Angles(phi, theta, psi);
1090
1091     update_ic();
1092     fgic->SetThetaRadIC(theta);
1093     fgic->SetPhiRadIC(phi);
1094     fgic->SetPsiRadIC(psi);
1095     needTrim=true;
1096 }
1097
1098 //Flight Path
1099 void FGJSBsim::set_Climb_Rate( double roc)
1100 {
1101     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Climb_Rate: " << roc );
1102
1103     // In case we're not trimming
1104     FGInterface::set_Climb_Rate(roc);
1105
1106     update_ic();
1107     //since both climb rate and flight path angle are set in the FG
1108     //startup sequence, something is needed to keep one from cancelling
1109     //out the other.
1110     if( !(fabs(roc) > 1 && fabs(fgic->GetFlightPathAngleRadIC()) < 0.01) ) {
1111       fgic->SetClimbRateFpsIC(roc);
1112     }
1113     needTrim=true;
1114 }
1115
1116 void FGJSBsim::set_Gamma_vert_rad( double gamma)
1117 {
1118     SG_LOG(SG_FLIGHT,SG_INFO, "FGJSBsim::set_Gamma_vert_rad: " << gamma );
1119
1120     update_ic();
1121     if( !(fabs(gamma) < 0.01 && fabs(fgic->GetClimbRateFpsIC()) > 1) ) {
1122       fgic->SetFlightPathAngleRadIC(gamma);
1123     }
1124     needTrim=true;
1125 }
1126
1127 void FGJSBsim::init_gear(void )
1128 {
1129     FGGroundReactions* gr=fdmex->GetGroundReactions();
1130     int Ngear=GroundReactions->GetNumGearUnits();
1131     for (int i=0;i<Ngear;i++) {
1132       FGLGear *gear = gr->GetGearUnit(i);
1133       SGPropertyNode * node = fgGetNode("gear/gear", i, true);
1134       node->setDoubleValue("xoffset-in", gear->GetBodyLocation()(1));
1135       node->setDoubleValue("yoffset-in", gear->GetBodyLocation()(2));
1136       node->setDoubleValue("zoffset-in", gear->GetBodyLocation()(3));
1137       node->setBoolValue("wow", gear->GetWOW());
1138       node->setDoubleValue("rollspeed-ms", gear->GetWheelRollVel()*0.3043);
1139       node->setBoolValue("has-brake", gear->GetBrakeGroup() > 0);
1140       node->setDoubleValue("position-norm", gear->GetGearUnitPos());
1141       node->setDoubleValue("tire-pressure-norm", gear->GetTirePressure());
1142       node->setDoubleValue("compression-norm", gear->GetCompLen());
1143       node->setDoubleValue("compression-ft", gear->GetCompLen());
1144       if ( gear->GetSteerable() )
1145         node->setDoubleValue("steering-norm", gear->GetSteerNorm());
1146     }
1147 }
1148
1149 void FGJSBsim::update_gear(void)
1150 {
1151     FGGroundReactions* gr=fdmex->GetGroundReactions();
1152     int Ngear=GroundReactions->GetNumGearUnits();
1153     for (int i=0;i<Ngear;i++) {
1154       FGLGear *gear = gr->GetGearUnit(i);
1155       SGPropertyNode * node = fgGetNode("gear/gear", i, true);
1156       node->getChild("wow", 0, true)->setBoolValue( gear->GetWOW());
1157       node->getChild("rollspeed-ms", 0, true)->setDoubleValue(gear->GetWheelRollVel()*0.3043);
1158       node->getChild("position-norm", 0, true)->setDoubleValue(gear->GetGearUnitPos());
1159       gear->SetTirePressure(node->getDoubleValue("tire-pressure-norm"));
1160       node->setDoubleValue("compression-norm", gear->GetCompLen());
1161       node->setDoubleValue("compression-ft", gear->GetCompLen());
1162       if ( gear->GetSteerable() )
1163         node->setDoubleValue("steering-norm", gear->GetSteerNorm());
1164     }
1165 }
1166
1167 void FGJSBsim::do_trim(void)
1168 {
1169   FGTrim *fgtrim;
1170
1171   if ( fgGetBool("/sim/presets/onground") )
1172   {
1173     fgtrim = new FGTrim(fdmex,tGround);
1174   } else {
1175     fgtrim = new FGTrim(fdmex,tLongitudinal);
1176   }
1177
1178   if ( !fgtrim->DoTrim() ) {
1179     fgtrim->Report();
1180     fgtrim->TrimStats();
1181   } else {
1182     trimmed->setBoolValue(true);
1183   }
1184   delete fgtrim;
1185
1186   pitch_trim->setDoubleValue( FCS->GetPitchTrimCmd() );
1187   throttle_trim->setDoubleValue( FCS->GetThrottleCmd(0) );
1188   aileron_trim->setDoubleValue( FCS->GetDaCmd() );
1189   rudder_trim->setDoubleValue( FCS->GetDrCmd() );
1190
1191   globals->get_controls()->set_elevator_trim(FCS->GetPitchTrimCmd());
1192   globals->get_controls()->set_elevator(FCS->GetDeCmd());
1193   globals->get_controls()->set_throttle(FGControls::ALL_ENGINES,
1194   FCS->GetThrottleCmd(0));
1195
1196   globals->get_controls()->set_aileron(FCS->GetDaCmd());
1197   globals->get_controls()->set_rudder( FCS->GetDrCmd());
1198
1199   SG_LOG( SG_FLIGHT, SG_INFO, "  Trim complete" );
1200 }
1201
1202 void FGJSBsim::update_ic(void)
1203 {
1204    if ( !needTrim ) {
1205      fgic->SetLatitudeRadIC(get_Lat_geocentric() );
1206      fgic->SetLongitudeRadIC( get_Longitude() );
1207      fgic->SetAltitudeASLFtIC( get_Altitude() );
1208      fgic->SetVcalibratedKtsIC( get_V_calibrated_kts() );
1209      fgic->SetThetaRadIC( get_Theta() );
1210      fgic->SetPhiRadIC( get_Phi() );
1211      fgic->SetPsiRadIC( get_Psi() );
1212      fgic->SetClimbRateFpsIC( get_Climb_Rate() );
1213    }
1214 }
1215
1216 bool
1217 FGJSBsim::get_agl_ft(double t, const double pt[3], double alt_off,
1218                      double contact[3], double normal[3], double vel[3],
1219                      double angularVel[3], double *agl)
1220 {
1221    const SGMaterial* material;
1222    simgear::BVHNode::Id id;
1223    if (!FGInterface::get_agl_ft(t, pt, alt_off, contact, normal, vel,
1224                                 angularVel, material, id))
1225        return false;
1226    SGGeod geodPt = SGGeod::fromCart(SG_FEET_TO_METER*SGVec3d(pt));
1227    SGQuatd hlToEc = SGQuatd::fromLonLat(geodPt);
1228    *agl = dot(hlToEc.rotate(SGVec3d(0, 0, 1)), SGVec3d(contact) - SGVec3d(pt));
1229    return true;
1230 }
1231
1232 inline static double dot3(const FGColumnVector3& a, const FGColumnVector3& b)
1233 {
1234     return a(1) * b(1) + a(2) * b(2) + a(3) * b(3);
1235 }
1236
1237 inline static double sqr(double x)
1238 {
1239     return x * x;
1240 }
1241
1242 static double angle_diff(double a, double b)
1243 {
1244     double diff = fabs(a - b);
1245     if (diff > 180) diff = 360 - diff;
1246
1247     return diff;
1248 }
1249
1250 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)
1251 {
1252     FGColumnVector3 tip(-hook_length * cos_fi_guess, 0, hook_length * sin_fi_guess);
1253     double dist = dot3(tip, ground_normal_body);
1254     if (fabs(dist + E) < 0.0001) {
1255         sin_fis[*points] = sin_fi_guess;
1256         cos_fis[*points] = cos_fi_guess;
1257         fis[*points] = atan2(sin_fi_guess, cos_fi_guess) * SG_RADIANS_TO_DEGREES;
1258         (*points)++;
1259     }
1260 }
1261
1262
1263 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)
1264 {
1265     if (sin_fi_guess >= -1 && sin_fi_guess <= 1) {
1266         double cos_fi_guess = sqrt(1 - sqr(sin_fi_guess));
1267         check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess, cos_fi_guess, sin_fis, cos_fis, fis, points);
1268         if (fabs(cos_fi_guess) > SG_EPSILON) {
1269             check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess, -cos_fi_guess, sin_fis, cos_fis, fis, points);
1270         }
1271     }
1272 }
1273
1274 void FGJSBsim::update_external_forces(double t_off)
1275 {
1276     const FGMatrix33& Tb2l = Propagate->GetTb2l();
1277     const FGMatrix33& Tl2b = Propagate->GetTl2b();
1278     const FGLocation& Location = Propagate->GetLocation();
1279     const FGMatrix33& Tec2l = Location.GetTec2l();
1280
1281     double hook_area[4][3];
1282
1283     FGColumnVector3 hook_root_body = MassBalance->StructuralToBody(hook_root_struct);
1284     FGColumnVector3 hook_root = Location.LocalToLocation(Tb2l *   hook_root_body);
1285     hook_area[1][0] = hook_root(1);
1286     hook_area[1][1] = hook_root(2);
1287     hook_area[1][2] = hook_root(3);
1288
1289     hook_length = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-length-ft", 6.75);
1290     double fi_min = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-min-deg", -18);
1291     double fi_max = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-max-deg", 30);
1292     double fi = fgGetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-norm") * (fi_max - fi_min) + fi_min;
1293     double cos_fi = cos(fi * SG_DEGREES_TO_RADIANS);
1294     double sin_fi = sin(fi * SG_DEGREES_TO_RADIANS);
1295
1296     FGColumnVector3 hook_tip_body = hook_root_body;
1297     hook_tip_body(1) -= hook_length * cos_fi;
1298     hook_tip_body(3) += hook_length * sin_fi;
1299
1300     double contact[3];
1301     double ground_normal[3];
1302     double ground_vel[3];
1303     double ground_angular_vel[3];
1304     double root_agl_ft;
1305
1306     if (!got_wire) {
1307         bool got = get_agl_ft(t_off, hook_area[1], 0, contact, ground_normal,
1308                               ground_vel, ground_angular_vel, &root_agl_ft);
1309         if (got && root_agl_ft > 0 && root_agl_ft < hook_length) {
1310             FGColumnVector3 ground_normal_body = Tl2b * (Tec2l * FGColumnVector3(ground_normal[0], ground_normal[1], ground_normal[2]));
1311             FGColumnVector3 contact_body = Tl2b * Location.LocationToLocal(FGColumnVector3(contact[0], contact[1], contact[2]));
1312             double D = -dot3(contact_body, ground_normal_body);
1313
1314             // check hook tip agl against same ground plane
1315             double hook_tip_agl_ft = dot3(hook_tip_body, ground_normal_body) + D;
1316             if (hook_tip_agl_ft < 0) {
1317
1318                 // hook tip: hx - l cos, hy, hz + l sin
1319                 // on ground:  - n0 l cos + n2 l sin + E = 0
1320
1321                 double E = D + dot3(hook_root_body, ground_normal_body);
1322
1323                 // substitue x = sin fi, cos fi = sqrt(1 - x * x)
1324                 // and rearrange to get a quadratic with coeffs:
1325                 double a = sqr(hook_length) * (sqr(ground_normal_body(1)) + sqr(ground_normal_body(3)));
1326                 double b = 2 * E * ground_normal_body(3) * hook_length;
1327                 double c = sqr(E) - sqr(ground_normal_body(1) * hook_length);
1328
1329                 double disc = sqr(b) - 4 * a * c;
1330                 if (disc >= 0) {
1331                     double delta = sqrt(disc) / (2 * a);
1332
1333                     // allow 4 solutions for safety, should never happen
1334                     double sin_fis[4];
1335                     double cos_fis[4];
1336                     double fis[4];
1337                     int points = 0;
1338
1339                     double sin_fi_guess = -b / (2 * a) - delta;
1340                     check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess, sin_fis, cos_fis, fis, &points);
1341                     check_hook_solution(ground_normal_body, E, hook_length, sin_fi_guess + 2 * delta, sin_fis, cos_fis, fis, &points);
1342
1343                     if (points == 2) {
1344                         double diff1 = angle_diff(fi, fis[0]);
1345                         double diff2 = angle_diff(fi, fis[1]);
1346                         int point = diff1 < diff2 ? 0 : 1;
1347                         fi = fis[point];
1348                         sin_fi = sin_fis[point];
1349                         cos_fi = cos_fis[point];
1350                         hook_tip_body(1) = hook_root_body(1) - hook_length * cos_fi;
1351                         hook_tip_body(3) = hook_root_body(3) + hook_length * sin_fi;
1352                     }
1353                 }
1354             }
1355         }
1356     } else {
1357         FGColumnVector3 hook_root_vel = Propagate->GetVel() + (Tb2l * (Propagate->GetPQR() *  hook_root_body));
1358         double wire_ends_ec[2][3];
1359         double wire_vel_ec[2][3];
1360         get_wire_ends_ft(t_off, wire_ends_ec, wire_vel_ec);
1361         FGColumnVector3 wire_vel_1 = Tec2l * FGColumnVector3(wire_vel_ec[0][0], wire_vel_ec[0][1], wire_vel_ec[0][2]);
1362         FGColumnVector3 wire_vel_2 = Tec2l * FGColumnVector3(wire_vel_ec[1][0], wire_vel_ec[1][1], wire_vel_ec[1][2]);
1363         FGColumnVector3 rel_vel = hook_root_vel - (wire_vel_1 + wire_vel_2) / 2;
1364         if (rel_vel.Magnitude() < 3) {
1365             got_wire = false;
1366             release_wire();
1367             fgSetDouble("/fdm/jsbsim/external_reactions/hook/magnitude", 0.0);
1368         } else {
1369             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;
1370             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;
1371             FGColumnVector3 force_plane_normal = wire_end1_body * wire_end2_body;
1372             force_plane_normal.Normalize();
1373             cos_fi = dot3(force_plane_normal, FGColumnVector3(0, 0, 1));
1374             if (cos_fi < 0) cos_fi = -cos_fi;
1375             sin_fi = sqrt(1 - sqr(cos_fi));
1376             fi = atan2(sin_fi, cos_fi) * SG_RADIANS_TO_DEGREES;
1377
1378             fgSetDouble("/fdm/jsbsim/external_reactions/hook/x", -cos_fi);
1379             fgSetDouble("/fdm/jsbsim/external_reactions/hook/y", 0);
1380             fgSetDouble("/fdm/jsbsim/external_reactions/hook/z", sin_fi);
1381             fgSetDouble("/fdm/jsbsim/external_reactions/hook/magnitude", fgGetDouble("/fdm/jsbsim/systems/hook/force"));
1382         }
1383     }
1384
1385     FGColumnVector3 hook_tip = Location.LocalToLocation(Tb2l * hook_tip_body);
1386
1387     hook_area[0][0] = hook_tip(1);
1388     hook_area[0][1] = hook_tip(2);
1389     hook_area[0][2] = hook_tip(3);
1390
1391     if (!got_wire) {
1392         // The previous positions.
1393         hook_area[2][0] = last_hook_root[0];
1394         hook_area[2][1] = last_hook_root[1];
1395         hook_area[2][2] = last_hook_root[2];
1396         hook_area[3][0] = last_hook_tip[0];
1397         hook_area[3][1] = last_hook_tip[1];
1398         hook_area[3][2] = last_hook_tip[2];
1399
1400         // Check if we caught a wire.
1401         // Returns true if we caught one.
1402         if (caught_wire_ft(t_off, hook_area)) {
1403                 got_wire = true;
1404         }
1405     }
1406
1407     // save actual position as old position ...
1408     last_hook_tip[0] = hook_area[0][0];
1409     last_hook_tip[1] = hook_area[0][1];
1410     last_hook_tip[2] = hook_area[0][2];
1411     last_hook_root[0] = hook_area[1][0];
1412     last_hook_root[1] = hook_area[1][1];
1413     last_hook_root[2] = hook_area[1][2];
1414
1415     fgSetDouble("/fdm/jsbsim/systems/hook/tailhook-pos-deg", fi);
1416 }
1417
1418
1419 void FGJSBsim::resetPropertyState()
1420 {
1421 // this code works-around bug #222:
1422 // http://code.google.com/p/flightgear-bugs/issues/detail?id=222
1423 // for whatever reason, having an existing value for the WOW
1424 // property causes the NaNs. Should that be fixed, this code can die
1425   SGPropertyNode* gear = fgGetNode("/fdm/jsbsim/gear", false);
1426   if (!gear) {
1427     return;
1428   }
1429
1430   int index = 0;
1431   SGPropertyNode* unitNode = NULL;
1432   for (; (unitNode = gear->getChild("unit", index)) != NULL; ++index) {
1433     unitNode->removeChild("WOW", 0, false);
1434   }
1435 }
1436