X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=src%2FSystems%2Fvacuum.cxx;h=a776d9a493d246a36561c57356a784fb1775fdc5;hb=e9a9f8c96d2963f28e4ecb4eaa91e47b52aaecf6;hp=19bde57773912bd073779970f47bd67dc4650bc6;hpb=682feb8f2d4803444b5a95d956de3979a7a7fcc7;p=flightgear.git

diff --git a/src/Systems/vacuum.cxx b/src/Systems/vacuum.cxx
index 19bde5777..a776d9a49 100644
--- a/src/Systems/vacuum.cxx
+++ b/src/Systems/vacuum.cxx
@@ -3,12 +3,28 @@
 //
 // This file is in the Public Domain and comes with no warranty.
 
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
 #include "vacuum.hxx"
+
+#include <cstring>
+
 #include <Main/fg_props.hxx>
 
 
-VacuumSystem::VacuumSystem ()
+VacuumSystem::VacuumSystem ( SGPropertyNode *node )
+    :
+    _name(node->getStringValue("name", "vacuum")),
+    _num(node->getIntValue("number", 0)),
+    _scale(node->getDoubleValue("scale", 1.0))
 {
+    for ( int i = 0; i < node->nChildren(); ++i ) {
+        SGPropertyNode *child = node->getChild(i);
+        if (!strcmp(child->getName(), "rpm"))
+            _rpms.push_back(child->getStringValue());
+    }
 }
 
 VacuumSystem::~VacuumSystem ()
@@ -16,14 +32,20 @@ VacuumSystem::~VacuumSystem ()
 }
 
 void
-VacuumSystem::init ()
+VacuumSystem::init()
 {
-                                // TODO: allow index of pump and engine
-                                // to be configured.
-    _serviceable_node = fgGetNode("/systems/vacuum[0]/serviceable", true);
-    _rpm_node = fgGetNode("/engines/engine[0]/rpm", true);
+    unsigned int i;
+    string branch;
+    branch = "/systems/" + _name;
+
+    SGPropertyNode *node = fgGetNode(branch.c_str(), _num, true );
+    _serviceable_node = node->getChild("serviceable", 0, true);
+    for ( i = 0; i < _rpms.size(); i++ ) {
+      SGPropertyNode_ptr _rpm_node = fgGetNode(_rpms[i].c_str(), true);
+      _rpm_nodes.push_back( _rpm_node );
+    }
     _pressure_node = fgGetNode("/environment/pressure-inhg", true);
-    _suction_node = fgGetNode("/systems/vacuum[0]/suction-inhg", true);
+    _suction_node = node->getChild("suction-inhg", 0, true);
 }
 
 void
@@ -42,15 +64,28 @@ VacuumSystem::update (double dt)
     // Model taken from steam.cxx
 
     double suction;
+    unsigned int i;
 
     if (!_serviceable_node->getBoolValue()) {
         suction = 0.0;
     } else {
-        double rpm = _rpm_node->getDoubleValue();
+	// select the source with the max rpm
+        double rpm = 0.0;
+	for ( i = 0; i < _rpm_nodes.size(); i++ ) {
+	  double tmp = _rpm_nodes[i]->getDoubleValue() * _scale;
+	  if ( tmp > rpm ) {
+	    rpm = tmp;
+	  }
+	}
         double pressure = _pressure_node->getDoubleValue();
-        suction = pressure * rpm / (rpm + 10000.0);
-        if (suction > 5.0)
-            suction = 5.0;
+        // This magic formula yields about 4 inhg at 700 rpm
+        suction = pressure * rpm / (rpm + 4875.0);
+
+        // simple regulator model that clamps smoothly to about 5 inhg
+        // over a normal rpm range
+        double max = (rpm > 0 ? 5.39 - 1.0 / ( rpm * 0.00111 ) : 0);
+        if ( suction < 0.0 ) suction = 0.0;
+        if ( suction > max ) suction = max;
     }
     _suction_node->setDoubleValue(suction);
 }