1 // electrical.cxx - a flexible, generic electrical system model.
3 // Written by Curtis Olson, started September 2002.
5 // Copyright (C) 2002 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/misc/exception.hxx>
25 #include <simgear/misc/sg_path.hxx>
27 #include <Main/fg_props.hxx>
28 #include <Main/globals.hxx>
30 #include "electrical.hxx"
33 FGElectricalComponent::FGElectricalComponent() :
41 FGElectricalSupplier::FGElectricalSupplier ( SGPropertyNode *node ) {
44 // cout << "Creating a supplier" << endl;
45 name = node->getStringValue("name");
46 string _model = node->getStringValue("kind");
47 // cout << "_model = " << _model << endl;
48 if ( _model == "battery" ) {
50 } else if ( _model == "alternator" ) {
51 model = FG_ALTERNATOR;
52 } else if ( _model == "external" ) {
57 volts = node->getDoubleValue("volts");
58 amps = node->getDoubleValue("amps");
61 for ( i = 0; i < node->nChildren(); ++i ) {
62 SGPropertyNode *child = node->getChild(i);
63 // cout << " scanning: " << child->getName() << endl;
64 if ( (string)child->getName() == "prop" ) {
65 string prop = child->getStringValue();
66 // cout << " Adding prop = " << prop << endl;
68 fgSetDouble( prop.c_str(), amps );
72 _rpm_node = fgGetNode("/engines/engine[0]/rpm", true);
76 double FGElectricalSupplier::get_output() {
77 if ( model == FG_BATTERY ) {
78 // cout << "battery amps = " << amps << endl;
80 } else if ( model == FG_ALTERNATOR ) {
81 // scale alternator output for rpms < 600. For rpms >= 600
82 // give full output. This is just a WAG, and probably not how
83 // it really works but I'm keeping things "simple" to start.
84 double rpm = _rpm_node->getDoubleValue();
85 double factor = rpm / 600.0;
89 // cout << "alternator amps = " << amps * factor << endl;
91 } else if ( model == FG_EXTERNAL ) {
92 // cout << "external amps = " << 0.0 << endl;
95 SG_LOG( SG_ALL, SG_ALERT, "unknown supplier type" );
102 FGElectricalBus::FGElectricalBus ( SGPropertyNode *node ) {
105 name = node->getStringValue("name");
107 for ( i = 0; i < node->nChildren(); ++i ) {
108 SGPropertyNode *child = node->getChild(i);
109 if ( (string)child->getName() == "prop" ) {
110 string prop = child->getStringValue();
117 FGElectricalOutput::FGElectricalOutput ( SGPropertyNode *node ) {
120 name = node->getStringValue("name");
122 for ( i = 0; i < node->nChildren(); ++i ) {
123 SGPropertyNode *child = node->getChild(i);
124 if ( (string)child->getName() == "prop" ) {
125 string prop = child->getStringValue();
132 FGElectricalConnector::FGElectricalConnector ( SGPropertyNode *node,
133 FGElectricalSystem *es ) {
137 for ( i = 0; i < node->nChildren(); ++i ) {
138 SGPropertyNode *child = node->getChild(i);
139 string cname = child->getName();
140 string cval = child->getStringValue();
141 // cout << " " << cname << " = " << cval << endl;
142 if ( cname == "input" ) {
143 FGElectricalComponent *s = es->find( child->getStringValue() );
146 if ( s->get_kind() == FG_SUPPLIER ) {
147 s->add_output( this );
148 } else if ( s->get_kind() == FG_BUS ) {
149 s->add_output( this );
151 SG_LOG( SG_ALL, SG_ALERT,
152 "Attempt to connect to something that can't provide an output: "
153 << child->getStringValue() );
156 SG_LOG( SG_ALL, SG_ALERT, "Can't find named source: "
157 << child->getStringValue() );
159 } else if ( cname == "output" ) {
160 FGElectricalComponent *s = es->find( child->getStringValue() );
163 if ( s->get_kind() == FG_BUS ) {
164 s->add_input( this );
165 } else if ( s->get_kind() == FG_OUTPUT ) {
166 s->add_input( this );
168 SG_LOG( SG_ALL, SG_ALERT,
169 "Attempt to connect to something that can't provide an input: "
170 << child->getStringValue() );
173 SG_LOG( SG_ALL, SG_ALERT, "Can't find named source: "
174 << child->getStringValue() );
176 } else if ( cname == "switch" ) {
177 // set default value of switch to true
178 // cout << "Switch = " << child->getStringValue() << endl;
179 fgSetBool( child->getStringValue(), true );
180 add_switch( fgGetNode( child->getStringValue(), true ) );
184 // do a 2nd pass to pick up starting switch value if specified
185 for ( i = 0; i < node->nChildren(); ++i ) {
186 SGPropertyNode *child = node->getChild(i);
187 string cname = child->getName();
188 string cval = child->getStringValue();
189 // cout << " " << cname << " = " << cval << endl;
190 if ( cname == "initial-state" ) {
191 if ( cval == "off" ) {
192 set_switches( false );
194 set_switches( true );
201 // set all switches to the specified state
202 void FGElectricalConnector::set_switches( bool state ) {
203 cout << "setting switch state to " << state << endl;
204 for ( unsigned int i = 0; i < switches.size(); ++i ) {
205 switches[i]->setBoolValue( state );
210 // return true if all switches are true, false otherwise. A connector
211 // could have multiple switches, but they all need to be true(closed)
212 // for current to get through.
213 bool FGElectricalConnector::get_state() {
215 for ( i = 0; i < switches.size(); ++i ) {
216 if ( ! switches[i]->getBoolValue() ) {
225 FGElectricalSystem::FGElectricalSystem () :
231 FGElectricalSystem::~FGElectricalSystem () {
235 void FGElectricalSystem::init () {
236 config_props = new SGPropertyNode;
238 SGPropertyNode *path_n = fgGetNode("/sim/systems/electrical/path");
241 SGPath config( globals->get_fg_root() );
242 config.append( path_n->getStringValue() );
244 SG_LOG( SG_ALL, SG_ALERT, "Reading electrical system model from "
247 readProperties( config.str(), config_props );
252 SG_LOG( SG_ALL, SG_ALERT,
253 "Detected an internal inconsistancy in the electrical");
254 SG_LOG( SG_ALL, SG_ALERT,
255 " system specification file. See earlier errors for" );
256 SG_LOG( SG_ALL, SG_ALERT,
260 } catch (const sg_exception& exc) {
261 SG_LOG( SG_ALL, SG_ALERT, "Failed to load electrical system model: "
266 SG_LOG( SG_ALL, SG_ALERT,
267 "No electrical model specified for this model!");
273 void FGElectricalSystem::bind () {
277 void FGElectricalSystem::unbind () {
281 void FGElectricalSystem::update (double dt) {
286 // cout << "Updating electrical system" << endl;
290 // zero everything out before we start
291 for ( i = 0; i < suppliers.size(); ++i ) {
292 suppliers[i]->set_value( 0.0 );
294 for ( i = 0; i < buses.size(); ++i ) {
295 buses[i]->set_value( 0.0 );
297 for ( i = 0; i < outputs.size(); ++i ) {
298 outputs[i]->set_value( 0.0 );
300 for ( i = 0; i < connectors.size(); ++i ) {
301 connectors[i]->set_value( 0.0 );
304 // for each supplier, propagate the electrical current
305 for ( i = 0; i < suppliers.size(); ++i ) {
306 // cout << " Updating: " << suppliers[i]->get_name() << endl;
307 propagate( suppliers[i], 0.0, " " );
313 bool FGElectricalSystem::build () {
314 SGPropertyNode *node;
317 int count = config_props->nChildren();
318 for ( i = 0; i < count; ++i ) {
319 node = config_props->getChild(i);
320 string name = node->getName();
321 // cout << name << endl;
322 if ( name == "supplier" ) {
323 FGElectricalSupplier *s =
324 new FGElectricalSupplier( node );
325 suppliers.push_back( s );
326 } else if ( name == "bus" ) {
328 new FGElectricalBus( node );
329 buses.push_back( b );
330 } else if ( name == "output" ) {
331 FGElectricalOutput *o =
332 new FGElectricalOutput( node );
333 outputs.push_back( o );
334 } else if ( name == "connector" ) {
335 FGElectricalConnector *c =
336 new FGElectricalConnector( node, this );
337 connectors.push_back( c );
339 SG_LOG( SG_ALL, SG_ALERT, "Unknown component type specified: "
349 // propagate the electrical current through the network
350 void FGElectricalSystem::propagate( FGElectricalComponent *node, double val,
354 // determine the current to carry forward
355 double current = 0.0;
356 if ( !fgGetBool("/systems/electrical/serviceable") ) {
358 } else if ( node->get_kind() == FG_SUPPLIER ) {
359 // cout << s << " is a supplier" << endl;
360 current = ((FGElectricalSupplier *)node)->get_output();
361 } else if ( node->get_kind() == FG_BUS ) {
362 // cout << s << " is a bus" << endl;
364 } else if ( node->get_kind() == FG_OUTPUT ) {
365 // cout << s << " is an output" << endl;
367 } else if ( node->get_kind() == FG_CONNECTOR ) {
368 // cout << s << " is a connector" << endl;
369 if ( ((FGElectricalConnector *)node)->get_state() ) {
374 // cout << s << " val = " << current << endl;
376 SG_LOG( SG_ALL, SG_ALERT, "unkown node type" );
379 if ( current > node->get_value() ) {
380 node->set_value( current );
385 // publish values to specified properties
386 for ( i = 0; i < node->get_num_props(); ++i ) {
387 fgSetDouble( node->get_prop(i).c_str(), node->get_value() );
389 // cout << s << node->get_name() << " -> " << node->get_value() << endl;
391 // propagate to all children
392 for ( i = 0; i < node->get_num_outputs(); ++i ) {
393 propagate( node->get_output(i), current, s );
398 // search for the named component and return a pointer to it, NULL otherwise
399 FGElectricalComponent *FGElectricalSystem::find ( const string &name ) {
404 for ( i = 0; i < suppliers.size(); ++i ) {
405 s = suppliers[i]->get_name();
406 // cout << " " << s << endl;
413 for ( i = 0; i < buses.size(); ++i ) {
414 s = buses[i]->get_name();
415 // cout << " " << s << endl;
421 // then search outputs
422 for ( i = 0; i < outputs.size(); ++i ) {
423 s = outputs[i]->get_name();
424 // cout << " " << s << endl;