X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=src%2FSystems%2Felectrical.cxx;h=b83984dd6cf986f0b18b21d02b1e81a718c29452;hb=46ec7a6ff78b0718c6eb09e5abb45c67c153d2f5;hp=a704a5a1f19321b9589edeab65991cb15ca48b96;hpb=8d2014f7bcf3a348271d5f4d1c0d02a9623c222a;p=flightgear.git diff --git a/src/Systems/electrical.cxx b/src/Systems/electrical.cxx index a704a5a1f..b83984dd6 100644 --- a/src/Systems/electrical.cxx +++ b/src/Systems/electrical.cxx @@ -2,7 +2,7 @@ // // Written by Curtis Olson, started September 2002. // -// Copyright (C) 2002 Curtis L. Olson - curt@flightgear.org +// Copyright (C) 2002 Curtis L. Olson - http://www.flightgear.org/~curt // // This program is free software; you can redistribute it and/or // modify it under the terms of the GNU General Public License as @@ -16,13 +16,21 @@ // // 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., 675 Mass Ave, Cambridge, MA 02139, USA. +// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. // // $Id$ +#ifdef HAVE_CONFIG_H +# include +#endif -#include +#include +#include + +#include #include +#include +#include #include
#include
@@ -33,97 +41,294 @@ FGElectricalComponent::FGElectricalComponent() : kind(-1), name(""), - prop(""), - value(0.0) + volts(0.0), + load_amps(0.0) { } -FGElectricalSupplier::FGElectricalSupplier ( string _name, string _prop, - string _model, - double _volts, double _amps ) -{ +FGElectricalSupplier::FGElectricalSupplier ( SGPropertyNode *node ) { kind = FG_SUPPLIER; - name = _name; - prop = _prop; + // cout << "Creating a supplier" << endl; + name = node->getStringValue("name"); + string _model = node->getStringValue("kind"); // cout << "_model = " << _model << endl; if ( _model == "battery" ) { model = FG_BATTERY; + amp_hours = node->getFloatValue("amp-hours", 40.0); + percent_remaining = node->getFloatValue("percent-remaining", 1.0); + charge_amps = node->getFloatValue("charge-amps", 7.0); } else if ( _model == "alternator" ) { model = FG_ALTERNATOR; + rpm_src = node->getStringValue("rpm-source"); + rpm_threshold = node->getFloatValue("rpm-threshold", 600.0); + ideal_amps = node->getFloatValue("amps", 60.0); } else if ( _model == "external" ) { model = FG_EXTERNAL; + ideal_amps = node->getFloatValue("amps", 60.0); } else { model = FG_UNKNOWN; } - volts = _volts; - amps = _amps; + ideal_volts = node->getFloatValue("volts"); - fgSetDouble( prop.c_str(), amps ); + int i; + for ( i = 0; i < node->nChildren(); ++i ) { + SGPropertyNode *child = node->getChild(i); + // cout << " scanning: " << child->getName() << endl; + if ( !strcmp(child->getName(), "prop") ) { + string prop = child->getStringValue(); + // cout << " Adding prop = " << prop << endl; + add_prop( prop ); + fgSetFloat( prop.c_str(), ideal_amps ); + } + } - _rpm_node = fgGetNode("/engines/engine[0]/rpm", true); + _rpm_node = fgGetNode( rpm_src.c_str(), true); } -double FGElectricalSupplier::get_output() { +float FGElectricalSupplier::apply_load( float amps, float dt ) { + if ( model == FG_BATTERY ) { + // calculate amp hours used + float amphrs_used = amps * dt / 3600.0; + + // calculate percent of total available capacity + float percent_used = amphrs_used / amp_hours; + percent_remaining -= percent_used; + if ( percent_remaining < 0.0 ) { + percent_remaining = 0.0; + } else if ( percent_remaining > 1.0 ) { + percent_remaining = 1.0; + } + // cout << "battery percent = " << percent_remaining << endl; + return amp_hours * percent_remaining; + } else if ( model == FG_ALTERNATOR ) { + // scale alternator output for rpms < 600. For rpms >= 600 + // give full output. This is just a WAG, and probably not how + // it really works but I'm keeping things "simple" to start. + float rpm = _rpm_node->getFloatValue(); + float factor = rpm / rpm_threshold; + if ( factor > 1.0 ) { + factor = 1.0; + } + // cout << "alternator amps = " << amps * factor << endl; + float available_amps = ideal_amps * factor; + return available_amps - amps; + } else if ( model == FG_EXTERNAL ) { + // cout << "external amps = " << 0.0 << endl; + float available_amps = ideal_amps; + return available_amps - amps; + } else { + SG_LOG( SG_SYSTEMS, SG_ALERT, "unknown supplier type" ); + } + + return 0.0; +} + + +float FGElectricalSupplier::get_output_volts() { if ( model == FG_BATTERY ) { // cout << "battery amps = " << amps << endl; - return amps; + float x = 1.0 - percent_remaining; + float tmp = -(3.0 * x - 1.0); + float factor = (tmp*tmp*tmp*tmp*tmp + 32) / 32; + // cout << "battery % = " << percent_remaining << + // " factor = " << factor << endl; + // percent_remaining -= 0.001; + return ideal_volts * factor; } else if ( model == FG_ALTERNATOR ) { // scale alternator output for rpms < 600. For rpms >= 600 - // give full output. This is just a WAG, but I'm keeping - // things simple to start. - double rpm = _rpm_node->getDoubleValue(); - double factor = rpm / 600.0; + // give full output. This is just a WAG, and probably not how + // it really works but I'm keeping things "simple" to start. + float rpm = _rpm_node->getFloatValue(); + float factor = rpm / rpm_threshold; if ( factor > 1.0 ) { factor = 1.0; } // cout << "alternator amps = " << amps * factor << endl; - return amps * factor; + return ideal_volts * factor; } else if ( model == FG_EXTERNAL ) { // cout << "external amps = " << 0.0 << endl; - return 0.0; + return ideal_volts; } else { - cout << "unknown supplier type" << endl; + SG_LOG( SG_SYSTEMS, SG_ALERT, "unknown supplier type" ); } return 0.0; } -FGElectricalBus::FGElectricalBus ( string _name, string _prop ) -{ +float FGElectricalSupplier::get_output_amps() { + if ( model == FG_BATTERY ) { + // cout << "battery amp_hours = " << amp_hours << endl; + + // This is a WAG, but produce enough amps to burn the entire + // battery in one minute. + return amp_hours * 60.0; + } else if ( model == FG_ALTERNATOR ) { + // scale alternator output for rpms < 600. For rpms >= 600 + // give full output. This is just a WAG, and probably not how + // it really works but I'm keeping things "simple" to start. + float rpm = _rpm_node->getFloatValue(); + float factor = rpm / rpm_threshold; + if ( factor > 1.0 ) { + factor = 1.0; + } + // cout << "alternator amps = " << ideal_amps * factor << endl; + return ideal_amps * factor; + } else if ( model == FG_EXTERNAL ) { + // cout << "external amps = " << 0.0 << endl; + return ideal_amps; + } else { + SG_LOG( SG_SYSTEMS, SG_ALERT, "unknown supplier type" ); + } + + return 0.0; +} + + +FGElectricalBus::FGElectricalBus ( SGPropertyNode *node ) { kind = FG_BUS; - name = _name; - prop = _prop; + name = node->getStringValue("name"); + int i; + for ( i = 0; i < node->nChildren(); ++i ) { + SGPropertyNode *child = node->getChild(i); + if ( !strcmp(child->getName(), "prop") ) { + string prop = child->getStringValue(); + add_prop( prop ); + } + } } -FGElectricalOutput::FGElectricalOutput ( string _name, string _prop ) -{ +FGElectricalOutput::FGElectricalOutput ( SGPropertyNode *node ) { kind = FG_OUTPUT; + load_amps = 0.1; // arbitrary default value + + name = node->getStringValue("name"); + SGPropertyNode *draw = node->getNode("rated-draw"); + if ( draw != NULL ) { + load_amps = draw->getFloatValue(); + } + // cout << "rated draw = " << output_amps << endl; - name = _name; - prop = _prop; + int i; + for ( i = 0; i < node->nChildren(); ++i ) { + SGPropertyNode *child = node->getChild(i); + if ( !strcmp(child->getName(), "prop") ) { + string prop = child->getStringValue(); + add_prop( prop ); + } + } } -FGElectricalConnector::FGElectricalConnector () +FGElectricalSwitch::FGElectricalSwitch( SGPropertyNode *node ) : + switch_node( NULL ), + rating_amps( 0.0f ), + circuit_breaker( false ) { + bool initial_state = true; + int i; + for ( i = 0; i < node->nChildren(); ++i ) { + SGPropertyNode *child = node->getChild(i); + string cname = child->getName(); + string cval = child->getStringValue(); + if ( cname == "prop" ) { + switch_node = fgGetNode( cval.c_str(), true ); + // cout << "switch node = " << cval << endl; + } else if ( cname == "initial-state" ) { + if ( cval == "off" || cval == "false" ) { + initial_state = false; + } + // cout << "initial state = " << initial_state << endl; + } else if ( cname == "rating-amps" ) { + rating_amps = atof( cval.c_str() ); + circuit_breaker = true; + // cout << "initial state = " << initial_state << endl; + } + } + + switch_node->setBoolValue( initial_state ); + // cout << " value = " << switch_node->getBoolValue() << endl; +} + + +FGElectricalConnector::FGElectricalConnector ( SGPropertyNode *node, + FGElectricalSystem *es ) { kind = FG_CONNECTOR; name = "connector"; + int i; + for ( i = 0; i < node->nChildren(); ++i ) { + SGPropertyNode *child = node->getChild(i); + string cname = child->getName(); + string cval = child->getStringValue(); + // cout << " " << cname << " = " << cval << endl; + if ( cname == "input" ) { + FGElectricalComponent *s = es->find( child->getStringValue() ); + if ( s != NULL ) { + add_input( s ); + if ( s->get_kind() == FG_SUPPLIER ) { + s->add_output( this ); + } else if ( s->get_kind() == FG_BUS ) { + s->add_output( this ); + } else { + SG_LOG( SG_SYSTEMS, SG_ALERT, + "Attempt to connect to something that can't provide an output: " + << child->getStringValue() ); + } + } else { + SG_LOG( SG_SYSTEMS, SG_ALERT, "Can't find named source: " + << child->getStringValue() ); + } + } else if ( cname == "output" ) { + FGElectricalComponent *s = es->find( child->getStringValue() ); + if ( s != NULL ) { + add_output( s ); + if ( s->get_kind() == FG_BUS ) { + s->add_input( this ); + } else if ( s->get_kind() == FG_OUTPUT ) { + s->add_input( this ); + } else if ( s->get_kind() == FG_SUPPLIER && + ((FGElectricalSupplier *)s)->get_model() + == FGElectricalSupplier::FG_BATTERY ) { + s->add_output( this ); + } else { + SG_LOG( SG_SYSTEMS, SG_ALERT, + "Attempt to connect to something that can't provide an input: " + << child->getStringValue() ); + } + } else { + SG_LOG( SG_SYSTEMS, SG_ALERT, "Can't find named source: " + << child->getStringValue() ); + } + } else if ( cname == "switch" ) { + // cout << "Switch = " << child->getStringValue() << endl; + FGElectricalSwitch s( child ); + add_switch( s ); + } + } } +// set all switches to the specified state +void FGElectricalConnector::set_switches( bool state ) { + // cout << "setting switch state to " << state << endl; + for ( unsigned int i = 0; i < switches.size(); ++i ) { + switches[i].set_state( state ); + } +} + + // return true if all switches are true, false otherwise. A connector // could have multiple switches, but they all need to be true(closed) // for current to get through. bool FGElectricalConnector::get_state() { unsigned int i; for ( i = 0; i < switches.size(); ++i ) { - if ( ! switches[i]->getBoolValue() ) { + if ( ! switches[i].get_state() ) { return false; } } @@ -132,7 +337,10 @@ bool FGElectricalConnector::get_state() { } -FGElectricalSystem::FGElectricalSystem () : +FGElectricalSystem::FGElectricalSystem ( SGPropertyNode *node ) : + name(node->getStringValue("name", "electrical")), + num(node->getIntValue("number", 0)), + path(node->getStringValue("path")), enabled(false) { } @@ -143,33 +351,58 @@ FGElectricalSystem::~FGElectricalSystem () { void FGElectricalSystem::init () { - config_props = new SGPropertyNode; - - SGPath config( globals->get_fg_root() ); - config.append( fgGetString("/systems/electrical/path") ); + SGPropertyNode_ptr config_props = new SGPropertyNode; + + _volts_out = fgGetNode( "/systems/electrical/volts", true ); + _amps_out = fgGetNode( "/systems/electrical/amps", true ); + + // allow the electrical system to be specified via the + // aircraft-set.xml file (for backwards compatibility) or through + // the aircraft-systems.xml file. If a -set.xml entry is + // specified, that overrides the system entry. + SGPropertyNode *path_n = fgGetNode("/sim/systems/electrical/path"); + if ( path_n ) { + if ( path.length() ) { + SG_LOG( SG_SYSTEMS, SG_INFO, + "NOTICE: System manager configuration specifies an " << + "electrical system: " << path << " but it is " << + "being overridden by the one specified in the -set.xml " << + "file: " << path_n->getStringValue() ); + } - SG_LOG( SG_ALL, SG_ALERT, "Reading electrical system model from " - << config.str() ); - try { - readProperties( config.str(), config_props ); + path = path_n->getStringValue(); + } - if ( build() ) { - enabled = true; - } else { - SG_LOG( SG_ALL, SG_ALERT, - "Detected an internal inconsistancy in the electrical" ); - SG_LOG( SG_ALL, SG_ALERT, - " system specification file. See earlier errors for" ); - SG_LOG( SG_ALL, SG_ALERT, - " details."); - exit(-1); - } - } catch (const sg_exception& exc) { - SG_LOG( SG_ALL, SG_ALERT, "Failed to load electrical system model: " + if ( path.length() ) { + SGPath config = globals->resolve_aircraft_path(path); +#if defined(ENABLE_DEV_WARNINGS) + // load an obsolete xml configuration + SG_LOG( SG_SYSTEMS, SG_WARN, + "Reading deprecated xml electrical system model from\n " << config.str() ); +#endif + try { + readProperties( config, config_props ); + + if ( build(config_props) ) { + enabled = true; + } else { + throw sg_exception("Logic error in electrical system file."); + } + } catch (const sg_exception&) { + SG_LOG( SG_SYSTEMS, SG_ALERT, + "Failed to load electrical system model: " + << config ); + } + } else { + SG_LOG( SG_SYSTEMS, SG_INFO, + "No xml-based electrical model specified for this model!"); + } + + if ( !enabled ) { + _amps_out->setDoubleValue(0); } - delete config_props; } @@ -186,36 +419,139 @@ void FGElectricalSystem::update (double dt) { return; } - // cout << "Updating electrical system" << endl; + // cout << "Updating electrical system, dt = " << dt << endl; unsigned int i; - // zero everything out before we start + // zero out the voltage before we start, but don't clear the + // requested load values. for ( i = 0; i < suppliers.size(); ++i ) { - suppliers[i]->set_value( 0.0 ); + suppliers[i]->set_volts( 0.0 ); } for ( i = 0; i < buses.size(); ++i ) { - buses[i]->set_value( 0.0 ); + buses[i]->set_volts( 0.0 ); } for ( i = 0; i < outputs.size(); ++i ) { - outputs[i]->set_value( 0.0 ); + outputs[i]->set_volts( 0.0 ); } for ( i = 0; i < connectors.size(); ++i ) { - connectors[i]->set_value( 0.0 ); + connectors[i]->set_volts( 0.0 ); + } + + // for each "external" supplier, propagate the electrical current + for ( i = 0; i < suppliers.size(); ++i ) { + FGElectricalSupplier *node = (FGElectricalSupplier *)suppliers[i]; + if ( node->get_model() == FGElectricalSupplier::FG_EXTERNAL ) { + float load; + // cout << "Starting propagation: " << suppliers[i]->get_name() + // << endl; + load = propagate( suppliers[i], dt, + node->get_output_volts(), + node->get_output_amps(), + " " ); + + if ( node->apply_load( load, dt ) < 0.0 ) { + SG_LOG(SG_SYSTEMS, SG_ALERT, + "Error drawing more current than available!"); + } + } } - // for each supplier, propogate the electrical current + // for each "alternator" supplier, propagate the electrical + // current for ( i = 0; i < suppliers.size(); ++i ) { - // cout << " Updating: " << suppliers[i]->get_name() << endl; - propogate( suppliers[i], 0.0, " " ); + FGElectricalSupplier *node = (FGElectricalSupplier *)suppliers[i]; + if ( node->get_model() == FGElectricalSupplier::FG_ALTERNATOR) { + float load; + // cout << "Starting propagation: " << suppliers[i]->get_name() + // << endl; + load = propagate( suppliers[i], dt, + node->get_output_volts(), + node->get_output_amps(), + " " ); + + if ( node->apply_load( load, dt ) < 0.0 ) { + SG_LOG(SG_SYSTEMS, SG_ALERT, + "Error drawing more current than available!"); + } + } } + // for each "battery" supplier, propagate the electrical + // current + for ( i = 0; i < suppliers.size(); ++i ) { + FGElectricalSupplier *node = (FGElectricalSupplier *)suppliers[i]; + if ( node->get_model() == FGElectricalSupplier::FG_BATTERY ) { + float load; + // cout << "Starting propagation: " << suppliers[i]->get_name() + // << endl; + load = propagate( suppliers[i], dt, + node->get_output_volts(), + node->get_output_amps(), + " " ); + // cout << "battery load = " << load << endl; + + if ( node->apply_load( load, dt ) < 0.0 ) { + SG_LOG(SG_SYSTEMS, SG_ALERT, + "Error drawing more current than available!"); + } + } + } + + float alt_norm + = fgGetFloat("/systems/electrical/suppliers/alternator") / 60.0; + + // impliment an extremely simplistic voltage model (assumes + // certain naming conventions in electrical system config) + // FIXME: we probably want to be able to feed power from all + // engines if they are running and the master-alt is switched on + float volts = 0.0; + if ( fgGetBool("/controls/engines/engine[0]/master-bat") ) { + volts = 24.0; + } + if ( fgGetBool("/controls/engines/engine[0]/master-alt") ) { + if ( fgGetFloat("/engines/engine[0]/rpm") > 800 ) { + float alt_contrib = 28.0; + if ( alt_contrib > volts ) { + volts = alt_contrib; + } + } else if ( fgGetFloat("/engines/engine[0]/rpm") > 200 ) { + float alt_contrib = 20.0; + if ( alt_contrib > volts ) { + volts = alt_contrib; + } + } + } + _volts_out->setFloatValue( volts ); + + // impliment an extremely simplistic amps model (assumes certain + // naming conventions in the electrical system config) ... FIXME: + // make this more generic + float amps = 0.0; + if ( fgGetBool("/controls/engines/engine[0]/master-bat") ) { + if ( fgGetBool("/controls/engines/engine[0]/master-alt") && + fgGetFloat("/engines/engine[0]/rpm") > 800 ) + { + amps += 40.0 * alt_norm; + } + amps -= 15.0; // normal load + if ( fgGetBool("/controls/switches/flashing-beacon") ) { + amps -= 7.5; + } + if ( fgGetBool("/controls/switches/nav-lights") ) { + amps -= 7.5; + } + if ( amps > 7.0 ) { + amps = 7.0; + } + } + _amps_out->setFloatValue( amps ); } -bool FGElectricalSystem::build () { +bool FGElectricalSystem::build (SGPropertyNode* config_props) { SGPropertyNode *node; - int i, j; + int i; int count = config_props->nChildren(); for ( i = 0; i < count; ++i ) { @@ -224,82 +560,22 @@ bool FGElectricalSystem::build () { // cout << name << endl; if ( name == "supplier" ) { FGElectricalSupplier *s = - new FGElectricalSupplier( node->getStringValue("name"), - node->getStringValue("prop"), - node->getStringValue("kind"), - node->getDoubleValue("volts"), - node->getDoubleValue("amps") ); + new FGElectricalSupplier( node ); suppliers.push_back( s ); } else if ( name == "bus" ) { FGElectricalBus *b = - new FGElectricalBus( node->getStringValue("name"), - node->getStringValue("prop") ); + new FGElectricalBus( node ); buses.push_back( b ); } else if ( name == "output" ) { FGElectricalOutput *o = - new FGElectricalOutput( node->getStringValue("name"), - node->getStringValue("prop") ); + new FGElectricalOutput( node ); outputs.push_back( o ); } else if ( name == "connector" ) { FGElectricalConnector *c = - new FGElectricalConnector(); + new FGElectricalConnector( node, this ); connectors.push_back( c ); - SGPropertyNode *child; - int ccount = node->nChildren(); - for ( j = 0; j < ccount; ++j ) { - child = node->getChild(j); - string cname = child->getName(); - string cval = child->getStringValue(); - // cout << " " << cname << " = " << cval << endl; - if ( cname == "input" ) { - FGElectricalComponent *s = find( child->getStringValue() ); - if ( s != NULL ) { - c->add_input( s ); - if ( s->get_kind() == FG_SUPPLIER ) { - s->add_output( c ); - } else if ( s->get_kind() == FG_BUS ) { - s->add_output( c ); - } else { - SG_LOG( SG_ALL, SG_ALERT, - "Attempt to connect to something that can't provide an output: " - << child->getStringValue() ); - return false; - } - } else { - SG_LOG( SG_ALL, SG_ALERT, - "Can't find named source: " - << child->getStringValue() ); - return false; - } - } else if ( cname == "output" ) { - FGElectricalComponent *s = find( child->getStringValue() ); - if ( s != NULL ) { - c->add_output( s ); - if ( s->get_kind() == FG_BUS ) { - s->add_input( c ); - } else if ( s->get_kind() == FG_OUTPUT ) { - s->add_input( c ); - } else { - SG_LOG( SG_ALL, SG_ALERT, - "Attempt to connect to something that can't provide an input: " - << child->getStringValue() ); - return false; - } - } else { - SG_LOG( SG_ALL, SG_ALERT, - "Can't find named source: " - << child->getStringValue() ); - return false; - } - } else if ( cname == "switch" ) { - // set default value of switch to true - // cout << "Switch = " << child->getStringValue() << endl; - fgSetBool( child->getStringValue(), true ); - c->add_switch( fgGetNode( child->getStringValue(), true ) ); - } - } } else { - SG_LOG( SG_ALL, SG_ALERT, "Unknown component type specified: " + SG_LOG( SG_SYSTEMS, SG_ALERT, "Unknown component type specified: " << name ); return false; } @@ -309,47 +585,100 @@ bool FGElectricalSystem::build () { } -// propogate the electrical current through the network -void FGElectricalSystem::propogate( FGElectricalComponent *node, double val, - string s ) { +// propagate the electrical current through the network, returns the +// total current drawn by the children of this node. +float FGElectricalSystem::propagate( FGElectricalComponent *node, double dt, + float input_volts, float input_amps, + string s ) { s += " "; + + float total_load = 0.0; // determine the current to carry forward - double current = 0.0; - if ( node->get_kind() == FG_SUPPLIER ) { - // cout << s << " is a supplier" << endl; - current = ((FGElectricalSupplier *)node)->get_output(); - } else if ( node->get_kind() == FG_BUS ) { - // cout << s << " is a bus" << endl; - current = val; - } else if ( node->get_kind() == FG_OUTPUT ) { - // cout << s << " is an output" << endl; - current = val; - } else if ( node->get_kind() == FG_CONNECTOR ) { - // cout << s << " is a connector" << endl; + float volts = 0.0; + if ( !fgGetBool("/systems/electrical/serviceable") ) { + volts = 0; + } else if ( node->get_kind() == FGElectricalComponent::FG_SUPPLIER ) { + // cout << s << "is a supplier (" << node->get_name() << ")" << endl; + FGElectricalSupplier *supplier = (FGElectricalSupplier *)node; + if ( supplier->get_model() == FGElectricalSupplier::FG_BATTERY ) { + // cout << s << " (and is a battery)" << endl; + float battery_volts = supplier->get_output_volts(); + if ( battery_volts < (input_volts - 0.1) ) { + // special handling of a battery charge condition + // cout << s << " (and is being charged) in v = " + // << input_volts << " current v = " << battery_volts + // << endl; + supplier->apply_load( -supplier->get_charge_amps(), dt ); + return supplier->get_charge_amps(); + } + } + volts = input_volts; + } else if ( node->get_kind() == FGElectricalComponent::FG_BUS ) { + // cout << s << "is a bus (" << node->get_name() << ")" << endl; + volts = input_volts; + } else if ( node->get_kind() == FGElectricalComponent::FG_OUTPUT ) { + // cout << s << "is an output (" << node->get_name() << ")" << endl; + volts = input_volts; + if ( volts > 1.0 ) { + // draw current if we have voltage + total_load = node->get_load_amps(); + } + } else if ( node->get_kind() == FGElectricalComponent::FG_CONNECTOR ) { + // cout << s << "is a connector (" << node->get_name() << ")" << endl; if ( ((FGElectricalConnector *)node)->get_state() ) { - current = val; + volts = input_volts; } else { - current = 0.0; + volts = 0.0; } - // cout << s << " val = " << current << endl; + // cout << s << " input_volts = " << volts << endl; } else { - cout << "unkown node type" << endl; + SG_LOG( SG_SYSTEMS, SG_ALERT, "unknown node type" ); } - if ( current > node->get_value() ) { - node->set_value( current ); - } + int i; - if ( ! node->get_prop().empty() ) { - fgSetDouble( node->get_prop().c_str(), node->get_value() ); - } - // cout << s << node->get_name() << " -> " << node->get_value() << endl; + // if this node has found a stronger power source, update the + // value and propagate to all children + if ( volts > node->get_volts() ) { + node->set_volts( volts ); + for ( i = 0; i < node->get_num_outputs(); ++i ) { + FGElectricalComponent *child = node->get_output(i); + // send current equal to load + total_load += propagate( child, dt, + volts, child->get_load_amps(), + s ); + } - // propogate to all children - int i; - for ( i = 0; i < node->get_num_outputs(); ++i ) { - propogate( node->get_output(i), current, s ); + // if not an output node, register the downstream current draw + // (sum of all children) with this node. If volts are zero, + // current draw should be zero. + if ( node->get_kind() != FGElectricalComponent::FG_OUTPUT ) { + node->set_load_amps( total_load ); + } + + node->set_available_amps( input_amps - total_load ); + + // publish values to specified properties + for ( i = 0; i < node->get_num_props(); ++i ) { + fgSetFloat( node->get_prop(i).c_str(), node->get_volts() ); + } + + /* + cout << s << node->get_name() << " -> (volts) " << node->get_volts() + << endl; + cout << s << node->get_name() << " -> (load amps) " << total_load + << endl; + cout << s << node->get_name() << " -> (input amps) " << input_amps + << endl; + cout << s << node->get_name() << " -> (extra amps) " + << node->get_available_amps() << endl; + */ + + return total_load; + } else { + // cout << s << "no further propagation" << endl; + return 0.0; } }