Initial revision of balloon simulator code.
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8 changed files with 802 additions and 7 deletions
218
src/FDM/Balloon.cxx
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218
src/FDM/Balloon.cxx
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/*****************************************************************************
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Module: BalloonSimInterface.cxx
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Author: Christian Mayer
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Date started: 07.10.99
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Called by:
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-------- Copyright (C) 1999 Christian Mayer (fgfs@christianmayer.de) --------
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This program is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free Software
|
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Foundation; either version 2 of the License, or (at your option) any later
|
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version.
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|
||||
This program is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
||||
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
|
||||
details.
|
||||
|
||||
You should have received a copy of the GNU General Public License along with
|
||||
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
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||||
Place - Suite 330, Boston, MA 02111-1307, USA.
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Further information about the GNU General Public License can also be found on
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the world wide web at http://www.gnu.org.
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FUNCTIONAL DESCRIPTION
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------------------------------------------------------------------------------
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Interface to the hot air balloon simulator
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HISTORY
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------------------------------------------------------------------------------
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01.09.1999 Christian Mayer Created
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*****************************************************************************/
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/****************************************************************************/
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/* INCLUDES */
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/****************************************************************************/
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#include <Include/compiler.h>
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#ifdef FG_MATH_EXCEPTION_CLASH
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# include <math.h>
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#endif
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#include STL_STRING
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#include <Aircraft/aircraft.hxx>
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#include <Controls/controls.hxx>
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#include <Debug/logstream.hxx>
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#include <Include/fg_constants.h>
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#include <Main/options.hxx>
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#include <Math/fg_geodesy.hxx>
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#include <Misc/fgpath.hxx>
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#include "Balloon.h"
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/****************************************************************************/
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/********************************** CODE ************************************/
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/****************************************************************************/
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// Initialize the BalloonSim flight model, dt is the time increment for
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// each subsequent iteration through the EOM
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int FGBalloonSim::init( double dt ) {
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sgVec3 temp;
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FG_LOG( FG_FLIGHT, FG_INFO, "Starting initializing BalloonSim" );
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FG_LOG( FG_FLIGHT, FG_INFO, " created a balloon" );
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//set the dt of the model
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current_balloon.set_dt(dt);
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//set position
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sgSetVec3( temp,
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get_Latitude(),
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get_Longitude(),
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get_Altitude() * FEET_TO_METER);
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current_balloon.setPosition( temp );
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//set Euler angles (?)
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sgSetVec3( temp,
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get_Phi(),
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get_Theta(),
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get_Psi() );
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current_balloon.setHPR( temp );
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//set velocities
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sgSetVec3( temp,
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current_options.get_uBody(),
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current_options.get_vBody(),
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current_options.get_wBody() );
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current_balloon.setVelocity( temp );
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FG_LOG( FG_FLIGHT, FG_INFO, "Finished initializing BalloonSim" );
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return 1;
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}
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// Run an iteration of the EOM (equations of motion)
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int FGBalloonSim::update( int multiloop ) {
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double save_alt = 0.0;
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// lets try to avoid really screwing up the BalloonSim model
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if ( get_Altitude() < -9000 ) {
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save_alt = get_Altitude();
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set_Altitude( 0.0 );
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}
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// set control positions
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current_balloon.set_burner_strength ( controls.get_elevator() ); /*controls.get_throttle( 0 )*/
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//not more implemented yet
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// Inform BalloonSim of the local terrain altitude
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current_balloon.setGroundLevel ( get_Runway_altitude() * FEET_TO_METER);
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// old -- FGInterface_2_JSBsim() not needed except for Init()
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// translate FG to JSBsim structure
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// FGInterface_2_JSBsim(f);
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// printf("FG_Altitude = %.2f\n", FG_Altitude * 0.3048);
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// printf("Altitude = %.2f\n", Altitude * 0.3048);
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// printf("Radius to Vehicle = %.2f\n", Radius_to_vehicle * 0.3048);
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/* FDMExec.GetState()->Setsim_time(State->Getsim_time()
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+ State->Getdt() * multiloop); */
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for ( int i = 0; i < multiloop; i++ ) {
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current_balloon.update();
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}
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// translate BalloonSim back to FG structure so that the
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// autopilot (and the rest of the sim can use the updated
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// values
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copy_from_BalloonSim();
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/*sgVec3 temp, temp2;
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current_balloon.getPosition( temp );
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current_balloon.getVelocity( temp2 );
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FG_LOG( FG_FLIGHT, FG_INFO, "T: " << current_balloon.getTemperature() <<
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" alt: " << temp[2] <<
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" gr_alt: " << get_Runway_altitude() <<
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" burner: " << controls.get_elevator() <<
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" v[2]: " << temp2[2]); */
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// but lets restore our original bogus altitude when we are done
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if ( save_alt < -9000.0 ) {
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set_Altitude( save_alt );
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}
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return 1;
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}
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// Convert from the FGInterface struct to the BalloonSim
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int FGBalloonSim::copy_to_BalloonSim() {
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return 1;
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}
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// Convert from the BalloonSim to the FGInterface struct
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int FGBalloonSim::copy_from_BalloonSim() {
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sgVec3 temp;
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// Velocities
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current_balloon.getVelocity( temp );
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set_Velocities_Local( temp[0], temp[1], temp[2] );
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/* ***FIXME*** */ set_V_equiv_kts( sgLengthVec3 ( temp ) );
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set_Omega_Body( 0.0, 0.0, 0.0 );
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// Positions
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current_balloon.getPosition( temp );
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double lat_geoc = temp[0];
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double lon = temp[1];
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double alt = temp[2] * METER_TO_FEET;
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double lat_geod, tmp_alt, sl_radius1, sl_radius2, tmp_lat_geoc;
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fgGeocToGeod( lat_geoc, EQUATORIAL_RADIUS_M + alt * FEET_TO_METER,
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&lat_geod, &tmp_alt, &sl_radius1 );
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fgGeodToGeoc( lat_geod, alt * FEET_TO_METER, &sl_radius2, &tmp_lat_geoc );
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FG_LOG( FG_FLIGHT, FG_DEBUG, "lon = " << lon << " lat_geod = " << lat_geod
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<< " lat_geoc = " << lat_geoc
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<< " alt = " << alt << " tmp_alt = " << tmp_alt * METER_TO_FEET
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<< " sl_radius1 = " << sl_radius1 * METER_TO_FEET
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<< " sl_radius2 = " << sl_radius2 * METER_TO_FEET
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<< " Equator = " << EQUATORIAL_RADIUS_FT );
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set_Geocentric_Position( lat_geoc, lon,
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sl_radius2 * METER_TO_FEET + alt );
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set_Geodetic_Position( lat_geod, lon, alt );
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current_balloon.getHPR( temp );
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set_Euler_Angles( temp[0], temp[1], temp[2] );
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set_Alpha( 0.0/*FDMExec.GetTranslation()->Getalpha()*/ );
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set_Beta( 0.0/*FDMExec.GetTranslation()->Getbeta()*/ );
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/* **FIXME*** */ set_Sea_level_radius( sl_radius2 * METER_TO_FEET );
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/* **FIXME*** */ set_Earth_position_angle( 0.0 );
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/* ***FIXME*** */ set_Runway_altitude( 0.0 );
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set_sin_lat_geocentric( lat_geoc );
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set_cos_lat_geocentric( lat_geoc );
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set_sin_cos_longitude( lon );
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set_sin_cos_latitude( lat_geod );
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return 0;
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}
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95
src/FDM/Balloon.h
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95
src/FDM/Balloon.h
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/*****************************************************************************
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Header: BalloonSimInterface.h
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Author: Christian Mayer
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Date started: 07.10.99
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-------- Copyright (C) 1999 Christian Mayer (fgfs@christianmayer.de) --------
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This program is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free Software
|
||||
Foundation; either version 2 of the License, or (at your option) any later
|
||||
version.
|
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|
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This program is distributed in the hope that it will be useful, but WITHOUT
|
||||
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
||||
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
|
||||
details.
|
||||
|
||||
You should have received a copy of the GNU General Public License along with
|
||||
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
|
||||
Place - Suite 330, Boston, MA 02111-1307, USA.
|
||||
|
||||
Further information about the GNU General Public License can also be found on
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||||
the world wide web at http://www.gnu.org.
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FUNCTIONAL DESCRIPTION
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------------------------------------------------------------------------------
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interface to the the hot air balloon simulator
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HISTORY
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------------------------------------------------------------------------------
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07.10.1999 Christian Mayer Created
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*****************************************************************************/
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/****************************************************************************/
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/* SENTRY */
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/****************************************************************************/
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#ifndef BalloonSimInterface_H
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#define BalloonSimInterface_H
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/****************************************************************************/
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/* INCLUDES */
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/****************************************************************************/
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#include <FDM/Balloon/BalloonSim.h>
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#include <Aircraft/aircraft.hxx>
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#include "flight.hxx"
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/****************************************************************************/
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/* DEFINES */
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/****************************************************************************/
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/****************************************************************************/
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/* DECLARATIONS */
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/****************************************************************************/
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// reset flight params to a specific position
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// int fgBalloonSimInit(double dt, FGInterface& f);
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// update position based on inputs, positions, velocities, etc.
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// int fgBalloonSimUpdate(FGInterface& f, int multiloop);
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// Convert from the FGInterface struct to the BalloonSim
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// int FGInterface_2_fgBalloonSim (FGInterface& f);
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// Convert from the BalloonSim to the FGInterface struct
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// int fgBalloonSim_2_FGInterface (FGInterface& f);
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class FGBalloonSim: public FGInterface {
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balloon current_balloon;
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public:
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// copy FDM state to BalloonSim structures
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int copy_to_BalloonSim();
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// copy FDM state from BalloonSim structures
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int copy_from_BalloonSim();
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// reset flight params to a specific position
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int init( double dt );
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// update position based on inputs, positions, velocities, etc.
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int update( int multiloop );
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};
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/****************************************************************************/
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#endif /*BalloonSimInterface_H*/
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357
src/FDM/Balloon/BalloonSim.cpp
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357
src/FDM/Balloon/BalloonSim.cpp
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/*****************************************************************************
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Module: BalloonSim.cpp
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Author: Christian Mayer
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Date started: 01.09.99
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Called by:
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-------- Copyright (C) 1999 Christian Mayer (fgfs@christianmayer.de) --------
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This program is free software; you can redistribute it and/or modify it under
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||||
the terms of the GNU General Public License as published by the Free Software
|
||||
Foundation; either version 2 of the License, or (at your option) any later
|
||||
version.
|
||||
|
||||
This program is distributed in the hope that it will be useful, but WITHOUT
|
||||
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
||||
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
|
||||
details.
|
||||
|
||||
You should have received a copy of the GNU General Public License along with
|
||||
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
|
||||
Place - Suite 330, Boston, MA 02111-1307, USA.
|
||||
|
||||
Further information about the GNU General Public License can also be found on
|
||||
the world wide web at http://www.gnu.org.
|
||||
|
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FUNCTIONAL DESCRIPTION
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------------------------------------------------------------------------------
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A hot air balloon simulator
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HISTORY
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------------------------------------------------------------------------------
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01.09.1999 Christian Mayer Created
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03.10.1999 Christian Mayer cleaned the code by moveing WeatherDatabase
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calls inside the update()
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*****************************************************************************/
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/****************************************************************************/
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/* INCLUDES */
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/****************************************************************************/
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#include <stdio.h>
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// #include <conio.h>
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#include <math.h>
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#include <Aircraft/aircraft.hxx>
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#include <Include/fg_constants.h>
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#include <Main/options.hxx>
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#include <WeatherCM/FGLocalWeatherDatabase.h>
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#include "BalloonSim.h"
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#include "sg.h"
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/****************************************************************************/
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/********************************** CODE ************************************/
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/****************************************************************************/
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/****************************************************************************/
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/* */
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/* Constructor: */
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/* Set the balloon model to some values that seem reasonable as I haven't */
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/* got much original values */
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/* */
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/****************************************************************************/
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balloon::balloon()
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{
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dt = 0.1;
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ground_level = 3400.0;
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sgSetVec3(gravity_vector, 0.0, 0.0, -9.81);
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sgSetVec3(velocity, 0.0, 0.0, 0.0);
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sgSetVec3(position, 0.0, 0.0, 0.0);
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sgSetVec3(hpr, 0.0, 0.0, 0.0);
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/************************************************************************/
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/* My balloon has a radius of 8.8 metres as that gives a envelope */
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/* volume of about 2854 m^3 which is about 77000 ft^3, a very common */
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/* size for hot air balloons */
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/************************************************************************/
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balloon_envelope_area = 4.0 * (8.8 * 8.8) * FG_PI;
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balloon_envelope_volume = (4.0/3.0) * (8.8 * 8.8 * 8.8) * FG_PI;
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wind_facing_area_of_balloon = FG_PI * (8.8 * 8.8);
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wind_facing_area_of_basket = 2.0; //guessed: 2 m^2
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cw_envelope=0.45; //a sphere in this case
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cw_basket=0.8;
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weight_of_total_fuel = 40.0; //big guess
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weight_of_envelope = 200.0; //big guess
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weight_of_basket = 40.0; //big guess
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weight_of_cargo = 750.0; //big guess
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fuel_left=1.0;
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max_flow_of_fuel_per_second=10.0*1.0/3600.0; //assuming 10% of one hour of total burn time
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current_burner_strength = 0.0; //the throttle
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lambda = 0.15; //for plasic
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l_of_the_envelope = 1.0/1000.0; //the thickness of the envelope (in m): 1mm
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T = 273.16 + 130.6; //Temperature in the envelope => still at ground level
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}
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void balloon::update()
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{
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/************************************************************************/
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/* I'm simplifying the balloon by reducing the simulation to two */
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/* points: */
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/* the center of the basket (CB) and the center of the envelope (CE) */
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/* */
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/* ce */
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/* I */
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/* I */
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/* cg (=center of gravity) */
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/* I */
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/* cb */
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/* */
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/* On each center are forces acting: gravity and wind resitance. CE */
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/* additionally got the lift (=> I need to calculate the weight of the */
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/* air inside, too) */
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/* */
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/* The weight of the air in the envelope is dependant of the tempera- */
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/* ture. This temperature is decreasing over the time that is dependant */
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/* of the insulation of the envelope material (lambda), the gas used */
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/* (air) and the wind speed. For a plane surface it's for air: */
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/* */
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/* alpha = 4.8 + 3.4*v with v < 5.0 m/s */
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/* */
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/* The value k that takes all of that into account is defined as: */
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/* */
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/* 1 / k = 1 / alpha1 + 1 / alpha2 + l / lambda */
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/* */
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/* with 'l' beeing the 'length' i.e. thickness of the insulator, alpha1 */
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/* the air inside and alpha2 the air outside of the envelope. So our k */
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/* is: */
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/* */
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/* k = 1 / [1/4.8 + 1/(4.8+3.4v) + l/lambda] */
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/* */
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/* The energy lost by this process is defined as: */
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/* */
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/* dQ = k * A * t * dT */
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/* */
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/* with Q being the energy, k that value defined above, A the total */
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/* area of the envelope, t the time (in hours) and dT the temperature */
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/* difference between the inside and the outside. */
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/* To get the temperature of the air in the inside I need the formula: */
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/* */
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/* dQ = cAir * m * dT */
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/* */
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/* with cAir being the specific heat capacity(?) of air (= 1.00 kcal / */
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/* kg * degree), m the mass of the air and dT the temperature change. */
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/* As the envelope is open I'm assuming that the same air pressure is */
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/* inside and outside of it (practical there should be a slightly */
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/* higher air pressure in the inside or the envelope would collapse). */
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/* So it's easy to calculate the density of the air inside: */
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/* */
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/* rho = p / R * T */
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/* */
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/* with p being the pressure, R the gas constant(?) which is for air */
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/* 287.14 N * m / kg * K and T the absolute temperature. */
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/* */
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/* The value returned by this function is the displacement of the CB */
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/************************************************************************/
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||||
|
||||
/************************************************************************/
|
||||
/* NOTE: This is the simplified version: I'm assuming that the whole */
|
||||
/* balloon consists only of the envelope.I will improove the simulation */
|
||||
/* later, but currently was my main concern to get it going... */
|
||||
/************************************************************************/
|
||||
|
||||
sgVec3 v;
|
||||
|
||||
//get the current wind velocity and store it in v
|
||||
Point3D temp = WeatherDatabase->get(position).Wind;
|
||||
sgSetVec3(v, temp.x(), temp.y(), temp.z());
|
||||
|
||||
sgSubVec3(v, velocity);
|
||||
float speed = sgLengthVec3(v);
|
||||
|
||||
// calculate the density of the gas inside
|
||||
double rho = WeatherDatabase->get(position).AirPressure / (287.14 * T);
|
||||
|
||||
// calculate the mass of the air
|
||||
double mAir = rho * balloon_envelope_volume;
|
||||
|
||||
// loss of energy by cooling down:
|
||||
float k = 1.0 / (1.0/4.8 + 1.0/(4.8+3.4*speed) + l_of_the_envelope/lambda);
|
||||
float Q = k * balloon_envelope_area * (dt/3600.0) * (WeatherDatabase->get(position).Temperature - T); //(dt/3600.0) = time since last call in hours
|
||||
|
||||
// gain of energy by heating:
|
||||
if (fuel_left > 0.0) //but only with some fuel left ;-)
|
||||
{
|
||||
float fuel_burning = current_burner_strength * max_flow_of_fuel_per_second * dt * weight_of_total_fuel; //in kg
|
||||
|
||||
//convert to cubemetres (I'm wrongly assuming 'normal' conditions; but that's correct for my special case)
|
||||
float cube_metres_burned = fuel_burning / 2.2; //2.2 is the density for propane
|
||||
|
||||
fuel_left -= fuel_burning / weight_of_total_fuel;
|
||||
|
||||
// get energy through burning.
|
||||
Q += 22250.0 * cube_metres_burned; //22250 for propan, 29500 would be butane and if you dare: 2580 would be hydrogen...
|
||||
}
|
||||
|
||||
// calculate the new temperature in the inside:
|
||||
T += Q / (1.00 * mAir);
|
||||
|
||||
//calculate the masses of the envelope and the basket
|
||||
float mEnvelope = mAir + weight_of_envelope;
|
||||
float mBasket = weight_of_total_fuel*fuel_left + weight_of_basket + weight_of_cargo;
|
||||
|
||||
float mTotal = mEnvelope + mBasket;
|
||||
|
||||
//calulate the forces
|
||||
sgVec3 fTotal, fFriction, fLift;
|
||||
|
||||
sgScaleVec3(fTotal, gravity_vector, mTotal);
|
||||
sgScaleVec3(fFriction, v, cw_envelope * wind_facing_area_of_balloon * WeatherDatabase->getAirDensity(position) * speed / 2.0); //wind resistance
|
||||
sgScaleVec3(fLift, gravity_vector, -balloon_envelope_volume * WeatherDatabase->get(position).AirPressure / (287.14 * WeatherDatabase->get(position).Temperature));
|
||||
|
||||
sgAddVec3(fTotal, fLift);
|
||||
sgAddVec3(fTotal, fFriction);
|
||||
|
||||
//claculate acceleration: a = F / m
|
||||
sgVec3 aTotal, vTotal, dTotal;
|
||||
|
||||
sgScaleVec3(aTotal, fTotal, 1.0 / mTotal);
|
||||
|
||||
//integrate the displacement: d = 0.5 * a * dt**2 + v * dt + d
|
||||
sgScaleVec3(vTotal, velocity, dt);
|
||||
sgScaleVec3(dTotal, aTotal, 0.5*dt*dt); sgAddVec3(dTotal, vTotal);
|
||||
|
||||
//integrate the velocity to 'velocity': v = a * dt + v
|
||||
sgScaleVec3(vTotal, aTotal, dt); sgAddVec3(velocity, vTotal);
|
||||
|
||||
/************************************************************************/
|
||||
/* VERY WRONG STUFF: it's just here to get some results to start with */
|
||||
/************************************************************************/
|
||||
|
||||
// care for the ground
|
||||
if (position[2] < (ground_level+0.001) )
|
||||
velocity[2] = ground_level;
|
||||
|
||||
//return results
|
||||
sgAddVec3(position, dTotal);
|
||||
|
||||
//cout << "BallonSim: T: " << (T-273.16) << " alt: " << position[2] << " ground: " << ground_level << " throttle: " << current_burner_strength << "\n";
|
||||
}
|
||||
|
||||
void balloon::set_burner_strength(const float bs)
|
||||
{
|
||||
if ((bs>=0.0) && (bs<=1.0))
|
||||
current_burner_strength = bs;
|
||||
}
|
||||
|
||||
void balloon::getVelocity(sgVec3 v) const
|
||||
{
|
||||
sgCopyVec3(v, velocity);
|
||||
}
|
||||
|
||||
void balloon::setVelocity(const sgVec3 v)
|
||||
{
|
||||
sgCopyVec3(velocity, v);
|
||||
}
|
||||
|
||||
void balloon::getPosition(sgVec3 v) const
|
||||
{
|
||||
sgCopyVec3(v, position);
|
||||
}
|
||||
|
||||
void balloon::setPosition(const sgVec3 v)
|
||||
{
|
||||
sgCopyVec3(position, v);
|
||||
}
|
||||
|
||||
void balloon::getHPR(sgVec3 angles) const //the balloon isn't allways exactly vertical
|
||||
{
|
||||
sgCopyVec3(angles, hpr);
|
||||
}
|
||||
|
||||
void balloon::setHPR(const sgVec3 angles) //the balloon isn't allways exactly vertical
|
||||
{
|
||||
sgCopyVec3(hpr, angles);
|
||||
}
|
||||
|
||||
void balloon::setGroundLevel(const float altitude)
|
||||
{
|
||||
ground_level = altitude;
|
||||
}
|
||||
|
||||
float balloon::getTemperature(void) const
|
||||
{
|
||||
return T;
|
||||
}
|
||||
|
||||
float balloon::getFuelLeft(void) const
|
||||
{
|
||||
return fuel_left;
|
||||
}
|
||||
|
||||
/*
|
||||
void main(void)
|
||||
{
|
||||
bool burner = true;
|
||||
balloon bal;
|
||||
bool exit = false;
|
||||
sgVec3 pos={0.0, 0.0, 0.0};
|
||||
char c;
|
||||
float acc_dt = 0.0;
|
||||
float alt;
|
||||
|
||||
bool hysteresis = false; // moving up
|
||||
for (;!exit;)
|
||||
{
|
||||
for (int i=0; i<100; i++)
|
||||
{
|
||||
bal.update(0.1); acc_dt += 0.1;
|
||||
bal.getPosition(pos);
|
||||
alt = pos[2];
|
||||
|
||||
if (alt > 3010)
|
||||
{
|
||||
hysteresis = true;
|
||||
burner = false;
|
||||
}
|
||||
if ((alt < 2990) && (hysteresis == true))
|
||||
{
|
||||
hysteresis = false;
|
||||
burner = true;
|
||||
}
|
||||
if ((bal.getTemperature()-273.16)>250.0)
|
||||
burner = false; //emergency
|
||||
}
|
||||
|
||||
// toogle burner
|
||||
c = getch();
|
||||
if (c==' ')
|
||||
burner=!burner;
|
||||
//if (c=='s')
|
||||
// show=!show;
|
||||
|
||||
//printf("Position: (%f/%f/%f), dP: (%f/%f/%f), burner: ", pos[0], pos[1], pos[2], dp[0], dp[1], dp[2]);
|
||||
printf("%f \t%f \t%f \t%f\n", acc_dt/60.0, bal.getTemperature()-273.16, pos[2], bal.getFuelLeft());
|
||||
if (burner==true)
|
||||
{
|
||||
//printf("on\n");
|
||||
bal.set_burner_strength(1.0);
|
||||
}
|
||||
else
|
||||
{
|
||||
//printf("off\n");
|
||||
bal.set_burner_strength(0.0);
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
*/
|
115
src/FDM/Balloon/BalloonSim.h
Normal file
115
src/FDM/Balloon/BalloonSim.h
Normal file
|
@ -0,0 +1,115 @@
|
|||
/*****************************************************************************
|
||||
|
||||
Header: BalloonSim.h
|
||||
Author: Christian Mayer
|
||||
Date started: 01.09.99
|
||||
|
||||
-------- Copyright (C) 1999 Christian Mayer (fgfs@christianmayer.de) --------
|
||||
|
||||
This program is free software; you can redistribute it and/or modify it under
|
||||
the terms of the GNU General Public License as published by the Free Software
|
||||
Foundation; either version 2 of the License, or (at your option) any later
|
||||
version.
|
||||
|
||||
This program is distributed in the hope that it will be useful, but WITHOUT
|
||||
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
||||
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
|
||||
details.
|
||||
|
||||
You should have received a copy of the GNU General Public License along with
|
||||
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
|
||||
Place - Suite 330, Boston, MA 02111-1307, USA.
|
||||
|
||||
Further information about the GNU General Public License can also be found on
|
||||
the world wide web at http://www.gnu.org.
|
||||
|
||||
FUNCTIONAL DESCRIPTION
|
||||
------------------------------------------------------------------------------
|
||||
Header for the hot air balloon simulator
|
||||
|
||||
HISTORY
|
||||
------------------------------------------------------------------------------
|
||||
01.09.1999 Christian Mayer Created
|
||||
03.10.1999 Christian Mayer cleaned the code by moveing WeatherDatabase
|
||||
calls inside the update()
|
||||
*****************************************************************************/
|
||||
|
||||
/****************************************************************************/
|
||||
/* SENTRY */
|
||||
/****************************************************************************/
|
||||
#ifndef BalloonSim_H
|
||||
#define BalloonSim_H
|
||||
|
||||
/****************************************************************************/
|
||||
/* INCLUDES */
|
||||
/****************************************************************************/
|
||||
#include <sg.h>
|
||||
|
||||
/****************************************************************************/
|
||||
/* DEFINES */
|
||||
/****************************************************************************/
|
||||
|
||||
/****************************************************************************/
|
||||
/* CLASS DECLARATION */
|
||||
/****************************************************************************/
|
||||
class balloon
|
||||
{
|
||||
private:
|
||||
float dt; //in s
|
||||
|
||||
sgVec3 gravity_vector; //in m/s*s
|
||||
sgVec3 hpr; //the balloon isn't allways exactly vertical (e.g. during gusts); normalized
|
||||
sgVec3 velocity; //current velocity; it gets iterated at each 'update'
|
||||
sgVec3 position; //current position in lat/lon/alt
|
||||
|
||||
float balloon_envelope_area; //area of the envelope
|
||||
float balloon_envelope_volume; //volume of the envelope
|
||||
|
||||
float wind_facing_area_of_balloon;
|
||||
float wind_facing_area_of_basket;
|
||||
|
||||
float cw_envelope; //wind resistance of the envelope
|
||||
float cw_basket; //wind resistance of the bakset
|
||||
|
||||
//all weights in kg
|
||||
float weight_of_total_fuel;
|
||||
float weight_of_envelope;
|
||||
float weight_of_basket; //weight of all the unmovable stuff such as the basket, the burner and the empty tanks
|
||||
float weight_of_cargo; //passengers and anything left (e.g. sand bags that are thrown away to give additional lift)
|
||||
|
||||
float fuel_left; //as a percentage
|
||||
float max_flow_of_fuel_per_second; //in percent per second
|
||||
float current_burner_strength;
|
||||
|
||||
float lambda; //waermeuebergangskoeffizient (heat transmission coefficent?!?) for the envelope
|
||||
float l_of_the_envelope; //the thickness of the envelope (in m)
|
||||
|
||||
float T; //tempereature inside the balloon
|
||||
|
||||
float ground_level;
|
||||
|
||||
public:
|
||||
balloon(); //constructor for initializing the balloon
|
||||
|
||||
void update(); //dt = time in seconds since last call
|
||||
void set_burner_strength(const float bs);
|
||||
|
||||
void getVelocity(sgVec3 v) const;
|
||||
void setVelocity(const sgVec3 v);
|
||||
|
||||
void getPosition(sgVec3 v) const;
|
||||
void setPosition(const sgVec3 v);
|
||||
|
||||
void getHPR(sgVec3 angles) const; //the balloon isn't allways exactly vertical
|
||||
void setHPR(const sgVec3 angles); //the balloon isn't allways exactly vertical
|
||||
|
||||
void setGroundLevel(const float altitude);
|
||||
|
||||
float getTemperature(void) const;
|
||||
float getFuelLeft(void) const;
|
||||
|
||||
void set_dt(const float new_dt) { dt = new_dt; }
|
||||
};
|
||||
|
||||
/****************************************************************************/
|
||||
#endif /*BalloonSim_H*/
|
5
src/FDM/Balloon/Makefile.am
Normal file
5
src/FDM/Balloon/Makefile.am
Normal file
|
@ -0,0 +1,5 @@
|
|||
noinst_LIBRARIES = libBalloon.a
|
||||
|
||||
libBalloon_a_SOURCES = BalloonSim.cpp BalloonSim.h
|
||||
|
||||
INCLUDES += -I$(top_builddir) -I$(top_builddir)/Lib -I$(top_builddir)/Simulator
|
|
@ -1,8 +1,10 @@
|
|||
SUBDIRS = External JSBsim LaRCsim Slew
|
||||
SUBDIRS = Balloon External JSBsim LaRCsim Slew
|
||||
|
||||
noinst_LIBRARIES = libFlight.a
|
||||
|
||||
libFlight_a_SOURCES = flight.cxx flight.hxx \
|
||||
libFlight_a_SOURCES = \
|
||||
Balloon.cxx Balloon.hxx \
|
||||
flight.cxx flight.hxx \
|
||||
JSBsim.cxx JSBsim.hxx \
|
||||
LaRCsim.cxx LaRCsim.hxx
|
||||
|
||||
|
|
|
@ -34,6 +34,7 @@
|
|||
#include "flight.hxx"
|
||||
#include "JSBsim.hxx"
|
||||
#include "LaRCsim.hxx"
|
||||
#include "Balloon.h"
|
||||
|
||||
|
||||
// base_fdm_state is the internal state that is updated in integer
|
||||
|
|
|
@ -120,13 +120,15 @@ public:
|
|||
// Jon S. Berndt's new FDM written from the ground up in C++
|
||||
FG_JSBSIM = 2,
|
||||
|
||||
// Christian's hot air balloon simulation
|
||||
FG_BALLOONSIM = 3,
|
||||
|
||||
// The following aren't implemented but are here to spark
|
||||
// thoughts and discussions, and maybe even action.
|
||||
FG_ACM = 3,
|
||||
FG_SUPER_SONIC = 4,
|
||||
FG_HELICOPTER = 5,
|
||||
FG_AUTOGYRO = 6,
|
||||
FG_BALLOON = 7,
|
||||
FG_ACM = 4,
|
||||
FG_SUPER_SONIC = 5,
|
||||
FG_HELICOPTER = 6,
|
||||
FG_AUTOGYRO = 7,
|
||||
FG_PARACHUTE = 8,
|
||||
|
||||
// Driven externally via a serial port, net, file, etc.
|
||||
|
|
Loading…
Reference in a new issue