1 // JSBsim.cxx -- interface to the JSBsim flight model
3 // Written by Curtis Olson, started February 1999.
5 // Copyright (C) 1999 Curtis L. Olson - curt@flightgear.org
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.
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.
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.
24 #include <simgear/compiler.h>
26 #ifdef FG_MATH_EXCEPTION_CLASH
32 #include <simgear/constants.h>
33 #include <simgear/debug/logstream.hxx>
34 #include <simgear/math/fg_geodesy.hxx>
35 #include <simgear/misc/fgpath.hxx>
37 #include <Aircraft/aircraft.hxx>
38 #include <Controls/controls.hxx>
39 #include <Main/options.hxx>
41 #include <FDM/JSBsim/FGFDMExec.h>
42 #include <FDM/JSBsim/FGAircraft.h>
43 #include <FDM/JSBsim/FGFCS.h>
44 #include <FDM/JSBsim/FGPosition.h>
45 #include <FDM/JSBsim/FGRotation.h>
46 #include <FDM/JSBsim/FGState.h>
47 #include <FDM/JSBsim/FGTranslation.h>
48 #include <FDM/JSBsim/FGAuxiliary.h>
49 #include <FDM/JSBsim/FGDefs.h>
54 // Initialize the JSBsim flight model, dt is the time increment for
55 // each subsequent iteration through the EOM
56 int FGJSBsim::init( double dt ) {
57 FG_LOG( FG_FLIGHT, FG_INFO, "Starting and initializing JSBsim" );
59 FG_LOG( FG_FLIGHT, FG_INFO, " created FDMExec" );
61 FGPath aircraft_path( current_options.get_fg_root() );
62 aircraft_path.append( "Aircraft" );
64 FGPath engine_path( current_options.get_fg_root() );
65 engine_path.append( "Engine" );
67 FDMExec.GetState()->Setdt( dt );
69 FDMExec.GetAircraft()->LoadAircraft( aircraft_path.str(),
71 current_options.get_aircraft() );
72 FG_LOG( FG_FLIGHT, FG_INFO, " loaded aircraft" <<
73 current_options.get_aircraft() );
75 FG_LOG( FG_FLIGHT, FG_INFO, "Initializing JSBsim with:" );
76 FG_LOG( FG_FLIGHT, FG_INFO, " U: " << current_options.get_uBody() );
77 FG_LOG( FG_FLIGHT, FG_INFO, " V: " <<current_options.get_vBody() );
78 FG_LOG( FG_FLIGHT, FG_INFO, " W: " <<current_options.get_wBody() );
79 FG_LOG( FG_FLIGHT, FG_INFO, " phi: " <<get_Phi() );
80 FG_LOG( FG_FLIGHT, FG_INFO, "theta: " << get_Theta() );
81 FG_LOG( FG_FLIGHT, FG_INFO, " psi: " << get_Psi() );
82 FG_LOG( FG_FLIGHT, FG_INFO, " lat: " << get_Latitude() );
83 FG_LOG( FG_FLIGHT, FG_INFO, " lon: " << get_Longitude() );
84 FG_LOG( FG_FLIGHT, FG_INFO, " alt: " << get_Altitude() );
86 FDMExec.GetState()->Initialize(
87 current_options.get_uBody(),
88 current_options.get_vBody(),
89 current_options.get_wBody(),
98 FG_LOG( FG_FLIGHT, FG_INFO, " loaded initial conditions" );
100 FG_LOG( FG_FLIGHT, FG_INFO, " set dt" );
102 FG_LOG( FG_FLIGHT, FG_INFO, "Finished initializing JSBsim" );
110 // Run an iteration of the EOM (equations of motion)
111 int FGJSBsim::update( int multiloop ) {
112 double save_alt = 0.0;
113 double time_step = (1.0 / current_options.get_model_hz()) * multiloop;
114 double start_elev = get_Altitude();
116 // lets try to avoid really screwing up the JSBsim model
117 if ( get_Altitude() < -9000 ) {
118 save_alt = get_Altitude();
122 // copy control positions into the JSBsim structure
124 FDMExec.GetFCS()->SetDaCmd( controls.get_aileron());
125 FDMExec.GetFCS()->SetDeCmd( controls.get_elevator()
126 + controls.get_elevator_trim() );
127 FDMExec.GetFCS()->SetDrCmd( controls.get_rudder());
128 FDMExec.GetFCS()->SetDfCmd( 0.0 );
129 FDMExec.GetFCS()->SetDsbCmd( 0.0 );
130 FDMExec.GetFCS()->SetDspCmd( 0.0 );
131 FDMExec.GetFCS()->SetThrottleCmd( FGControls::ALL_ENGINES,
132 controls.get_throttle( 0 ) * 100.0 );
133 FDMExec.GetFCS()->SetThrottlePos( FGControls::ALL_ENGINES,
134 controls.get_throttle( 0 ) * 100.0 );
135 // FCS->SetBrake( controls.get_brake( 0 ) );
137 // Inform JSBsim of the local terrain altitude
138 // Runway_altitude = get_Runway_altitude();
140 // old -- FGInterface_2_JSBsim() not needed except for Init()
141 // translate FG to JSBsim structure
142 // FGInterface_2_JSBsim(f);
143 // printf("FG_Altitude = %.2f\n", FG_Altitude * 0.3048);
144 // printf("Altitude = %.2f\n", Altitude * 0.3048);
145 // printf("Radius to Vehicle = %.2f\n", Radius_to_vehicle * 0.3048);
147 /* FDMExec.GetState()->Setsim_time(State->Getsim_time()
148 + State->Getdt() * multiloop); */
150 for ( int i = 0; i < multiloop; i++ ) {
154 // printf("%d FG_Altitude = %.2f\n", i, FG_Altitude * 0.3048);
155 // printf("%d Altitude = %.2f\n", i, Altitude * 0.3048);
157 // translate JSBsim back to FG structure so that the
158 // autopilot (and the rest of the sim can use the updated
163 // but lets restore our original bogus altitude when we are done
164 if ( save_alt < -9000.0 ) {
165 set_Altitude( save_alt );
168 double end_elev = get_Altitude();
169 if ( time_step > 0.0 ) {
171 set_Climb_Rate( (end_elev - start_elev) / time_step );
178 // Convert from the FGInterface struct to the JSBsim generic_ struct
179 int FGJSBsim::copy_to_JSBsim() {
184 // Convert from the JSBsim generic_ struct to the FGInterface struct
185 int FGJSBsim::copy_from_JSBsim() {
188 set_Velocities_Local( FDMExec.GetPosition()->GetVn(),
189 FDMExec.GetPosition()->GetVe(),
190 FDMExec.GetPosition()->GetVd() );
191 // set_Velocities_Ground( V_north_rel_ground, V_east_rel_ground,
192 // V_down_rel_ground );
193 // set_Velocities_Local_Airmass( V_north_airmass, V_east_airmass,
195 // set_Velocities_Local_Rel_Airmass( V_north_rel_airmass,
196 // V_east_rel_airmass, V_down_rel_airmass );
197 // set_Velocities_Gust( U_gust, V_gust, W_gust );
198 // set_Velocities_Wind_Body( U_body, V_body, W_body );
200 // set_V_rel_wind( V_rel_wind );
201 // set_V_true_kts( V_true_kts );
202 // set_V_rel_ground( V_rel_ground );
203 // set_V_inertial( V_inertial );
204 // set_V_ground_speed( V_ground_speed );
205 // set_V_equiv( V_equiv );
207 set_V_equiv_kts( FDMExec.GetAuxiliary()->GetVequivalentKTS() );
208 //set_V_calibrated( FDMExec.GetAuxiliary()->GetVcalibratedFPS() );
209 set_V_calibrated_kts( FDMExec.GetAuxiliary()->GetVcalibratedKTS() );
211 set_Omega_Body( FDMExec.GetState()->GetParameter(FG_ROLLRATE),
212 FDMExec.GetState()->GetParameter(FG_PITCHRATE),
213 FDMExec.GetState()->GetParameter(FG_YAWRATE) );
214 // set_Omega_Local( P_local, Q_local, R_local );
215 // set_Omega_Total( P_total, Q_total, R_total );
217 set_Euler_Rates( FDMExec.GetRotation()->Getphi(),
218 FDMExec.GetRotation()->Gettht(),
219 FDMExec.GetRotation()->Getpsi() );
221 // ***FIXME*** set_Geocentric_Rates( Latitude_dot, Longitude_dot, Radius_dot );
223 set_Mach_number( FDMExec.GetTranslation()->GetMach());
226 double lat_geoc = FDMExec.GetPosition()->GetLatitude();
227 double lon = FDMExec.GetPosition()->GetLongitude();
228 double alt = FDMExec.GetPosition()->Geth();
229 double lat_geod, tmp_alt, sl_radius1, sl_radius2, tmp_lat_geoc;
230 fgGeocToGeod( lat_geoc, EQUATORIAL_RADIUS_M + alt * FEET_TO_METER,
231 &lat_geod, &tmp_alt, &sl_radius1 );
232 fgGeodToGeoc( lat_geod, alt * FEET_TO_METER, &sl_radius2, &tmp_lat_geoc );
234 FG_LOG( FG_FLIGHT, FG_DEBUG, "lon = " << lon << " lat_geod = " << lat_geod
235 << " lat_geoc = " << lat_geoc
236 << " alt = " << alt << " tmp_alt = " << tmp_alt * METER_TO_FEET
237 << " sl_radius1 = " << sl_radius1 * METER_TO_FEET
238 << " sl_radius2 = " << sl_radius2 * METER_TO_FEET
239 << " Equator = " << EQUATORIAL_RADIUS_FT );
241 set_Geocentric_Position( lat_geoc, lon,
242 sl_radius2 * METER_TO_FEET + alt );
243 set_Geodetic_Position( lat_geod, lon, alt );
244 set_Euler_Angles( FDMExec.GetRotation()->Getphi(),
245 FDMExec.GetRotation()->Gettht(),
246 FDMExec.GetRotation()->Getpsi() );
248 // Miscellaneous quantities
249 // set_T_Local_to_Body(T_local_to_body_m);
250 // set_Gravity( Gravity );
251 // set_Centrifugal_relief( Centrifugal_relief );
253 set_Alpha( FDMExec.GetTranslation()->Getalpha() );
254 set_Beta( FDMExec.GetTranslation()->Getbeta() );
255 // set_Alpha_dot( Alpha_dot );
256 // set_Beta_dot( Beta_dot );
258 // set_Cos_alpha( Cos_alpha );
259 // set_Sin_alpha( Sin_alpha );
260 // set_Cos_beta( Cos_beta );
261 // set_Sin_beta( Sin_beta );
263 // set_Cos_phi( Cos_phi );
264 // set_Sin_phi( Sin_phi );
265 // set_Cos_theta( Cos_theta );
266 // set_Sin_theta( Sin_theta );
267 // set_Cos_psi( Cos_psi );
268 // set_Sin_psi( Sin_psi );
270 // ***ATTENDTOME*** set_Gamma_vert_rad( Gamma_vert_rad );
271 // set_Gamma_horiz_rad( Gamma_horiz_rad );
273 // set_Sigma( Sigma );
274 // set_Density( Density );
275 // set_V_sound( V_sound );
276 // set_Mach_number( Mach_number );
278 // set_Static_pressure( Static_pressure );
279 // set_Total_pressure( Total_pressure );
280 // set_Impact_pressure( Impact_pressure );
281 // set_Dynamic_pressure( Dynamic_pressure );
283 // set_Static_temperature( Static_temperature );
284 // set_Total_temperature( Total_temperature );
286 /* **FIXME*** */ set_Sea_level_radius( sl_radius2 * METER_TO_FEET );
287 /* **FIXME*** */ set_Earth_position_angle( 0.0 );
289 /* ***FIXME*** */ set_Runway_altitude( 0.0 );
290 // set_Runway_latitude( Runway_latitude );
291 // set_Runway_longitude( Runway_longitude );
292 // set_Runway_heading( Runway_heading );
293 // set_Radius_to_rwy( Radius_to_rwy );
295 // set_CG_Rwy_Local( D_cg_north_of_rwy, D_cg_east_of_rwy, D_cg_above_rwy);
296 // set_CG_Rwy_Rwy( X_cg_rwy, Y_cg_rwy, H_cg_rwy );
297 // set_Pilot_Rwy_Local( D_pilot_north_of_rwy, D_pilot_east_of_rwy,
298 // D_pilot_above_rwy );
299 // set_Pilot_Rwy_Rwy( X_pilot_rwy, Y_pilot_rwy, H_pilot_rwy );
301 set_sin_lat_geocentric( lat_geoc );
302 set_cos_lat_geocentric( lat_geoc );
303 set_sin_cos_longitude( lon );
304 set_sin_cos_latitude( lat_geod );