X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=src%2FAIModel%2FAIBallistic.cxx;h=027196d113948482777f6f735321f1924cc3e662;hb=4bfd1722df24f5be89459b25010e5d7352720a7b;hp=e06bf9f4b9b858260c0f3368571e279436a98b1a;hpb=af284e4bb922a3782c9bd9d947895e787e41adbf;p=flightgear.git

diff --git a/src/AIModel/AIBallistic.cxx b/src/AIModel/AIBallistic.cxx
index e06bf9f4b..027196d11 100644
--- a/src/AIModel/AIBallistic.cxx
+++ b/src/AIModel/AIBallistic.cxx
@@ -27,32 +27,57 @@
 #include "AIBallistic.hxx"
 
 
-FGAIBallistic::FGAIBallistic(FGAIManager* mgr) {
-    manager = mgr;
-    _type_str = "ballistic";
-    _otype = otBallistic;
+FGAIBallistic::FGAIBallistic() : FGAIBase(otBallistic) {
     drag_area = 0.007;
     life_timer = 0.0;
+    gravity = 32;
+//  buoyancy = 64;
+    no_roll = false;
+    aero_stabilised = false;
 }
 
 FGAIBallistic::~FGAIBallistic() {
 }
 
+void FGAIBallistic::readFromScenario(SGPropertyNode* scFileNode) {
+  if (!scFileNode)
+    return;
+
+  FGAIBase::readFromScenario(scFileNode);
+
+  setAzimuth(scFileNode->getDoubleValue("azimuth", 0.0));
+  setElevation(scFileNode->getDoubleValue("elevation", 0.0));
+  setDragArea(scFileNode->getDoubleValue("eda", 0.007));
+  setLife(scFileNode->getDoubleValue("life", 900.0));
+  setBuoyancy(scFileNode->getDoubleValue("buoyancy", 0));
+  setWind_from_east(scFileNode->getDoubleValue("wind_from_east", 0));
+  setWind_from_north(scFileNode->getDoubleValue("wind_from_north", 0));
+  setWind(scFileNode->getBoolValue("wind", false));
+  setRoll(scFileNode->getDoubleValue("roll", 0.0));
+  setCd(scFileNode->getDoubleValue("cd", 0.029));
+  setMass(scFileNode->getDoubleValue("mass", 0.007));
+  setStabilisation(scFileNode->getBoolValue("aero_stabilized", false));
+}
 
 bool FGAIBallistic::init() {
    FGAIBase::init();
-   aero_stabilized =  true;
    hdg = azimuth;
    pitch = elevation;
+   roll = rotation;
+   Transform();
    return true;
 }
 
 void FGAIBallistic::bind() {
 //    FGAIBase::bind();
+   props->tie("sim/time/elapsed-sec",
+               SGRawValueMethods<FGAIBallistic,double>(*this,
+                                          &FGAIBallistic::_getTime));
 }
 
 void FGAIBallistic::unbind() {
 //    FGAIBase::unbind();
+   props->untie("sim/time/elapsed-sec");
 }
 
 void FGAIBallistic::update(double dt) {
@@ -71,9 +96,12 @@ void FGAIBallistic::setElevation(double el) {
    pitch = elevation = el;
 }
 
+void FGAIBallistic::setRoll(double rl) {
+   rotation = rl;
+}
 
-void FGAIBallistic::setStabilization(bool val) {
-   aero_stabilized = val;
+void FGAIBallistic::setStabilisation(bool val) {
+   aero_stabilised = val;
 }
 
 void FGAIBallistic::setDragArea(double a) {
@@ -84,39 +112,93 @@ void FGAIBallistic::setLife(double seconds) {
    life = seconds;
 }
 
+void FGAIBallistic::setBuoyancy(double fpss) {
+   buoyancy = fpss;
+}
+
+void FGAIBallistic::setWind_from_east(double fps) {
+   wind_from_east = fps;
+}
+
+void FGAIBallistic::setWind_from_north(double fps) {
+   wind_from_north = fps;
+}
+
+void FGAIBallistic::setWind(bool val) {
+   wind = val;
+}
+
+void FGAIBallistic::setCd(double c) {
+   Cd = c;
+}
+
+void FGAIBallistic::setMass(double m) {
+   mass = m;
+}
+
 void FGAIBallistic::Run(double dt) {
 
    life_timer += dt;
+//    cout << "life timer 1" << life_timer <<  dt << endl;
    if (life_timer > life) setDie(true); 
 
    double speed_north_deg_sec;
    double speed_east_deg_sec;
-
-   // the two drag calculations below assume sea-level density, 
-   // mass of 0.03 slugs,  drag coeff of 0.295
-   // adjust speed due to drag 
-   speed -= 0.0116918 * drag_area * speed * speed * dt;
+   double wind_speed_from_north_deg_sec;
+   double wind_speed_from_east_deg_sec;
+   double Cdm;      // Cd adjusted by Mach Number
+   
+   // Adjust Cd by Mach number. The equations are based on curves
+   // for a conventional shell/bullet (no boat-tail). 
+   if ( Mach < 0.7 ) { Cdm = 0.0125 * Mach + Cd; }
+     else if ( 0.7 < Mach && Mach < 1.2 ) { 
+       Cdm = 0.3742 * pow ( Mach, 2) - 0.252 * Mach + 0.0021 + Cd; }
+     else { Cdm = 0.2965 * pow ( Mach, -1.1506 ) + Cd; }
+
+//   cout << " Mach , " << Mach << " , Cdm , " << Cdm << endl;
+   
+   // drag = Cd * 0.5 * rho * speed * speed * drag_area;
+   // rho is adjusted for altitude in void FGAIBase::update,
+   // using Standard Atmosphere (sealevel temperature 15C)
+   // acceleration = drag/mass;
+   // adjust speed by drag
+   speed -= (Cdm * 0.5 * rho * speed * speed * drag_area/mass) * dt; 
+
+   // don't let speed become negative
    if ( speed < 0.0 ) speed = 0.0;
+   
+   // calculate vertical and horizontal speed components
    vs = sin( pitch * SG_DEGREES_TO_RADIANS ) * speed;
    hs = cos( pitch * SG_DEGREES_TO_RADIANS ) * speed;
 
    // convert horizontal speed (fps) to degrees per second
    speed_north_deg_sec = cos(hdg / SG_RADIANS_TO_DEGREES) * hs / ft_per_deg_lat;
    speed_east_deg_sec  = sin(hdg / SG_RADIANS_TO_DEGREES) * hs / ft_per_deg_lon;
-
+   
+   // if wind not required, set to zero
+   if (!wind) {
+      wind_from_north = 0;
+      wind_from_east = 0;
+   }
+  
+   // convert wind speed (fps) to degrees per second
+   wind_speed_from_north_deg_sec = wind_from_north / ft_per_deg_lat;
+   wind_speed_from_east_deg_sec  = wind_from_east / ft_per_deg_lon;
+   
    // set new position
-   pos.setlat( pos.lat() + speed_north_deg_sec * dt);
-   pos.setlon( pos.lon() + speed_east_deg_sec * dt); 
+   pos.setlat( pos.lat() + (speed_north_deg_sec - wind_speed_from_north_deg_sec) * dt );
+   pos.setlon( pos.lon() + (speed_east_deg_sec - wind_speed_from_east_deg_sec) * dt ); 
 
+   // adjust vertical speed for acceleration of gravity and buoyancy
+   vs -= (gravity - buoyancy) * dt;
+   
    // adjust altitude (feet)
    altitude += vs * dt;
    pos.setelev(altitude * SG_FEET_TO_METER); 
 
-   // adjust vertical speed for acceleration of gravity
-   vs -= 32.17 * dt;
-
    // recalculate pitch (velocity vector) if aerostabilized
-   if (aero_stabilized) pitch = atan2( vs, hs ) * SG_RADIANS_TO_DEGREES;
+   //   cout << "aero_stabilised " << aero_stabilised  << endl ;
+   if (aero_stabilised) pitch = atan2( vs, hs ) * SG_RADIANS_TO_DEGREES;
 
    // recalculate total speed
    speed = sqrt( vs * vs + hs * hs);
@@ -124,5 +206,11 @@ void FGAIBallistic::Run(double dt) {
    // set destruction flag if altitude less than sea level -1000
    if (altitude < -1000.0) setDie(true);
 
+}  // end Run
+
+double FGAIBallistic::_getTime() const {
+//    cout << "life timer 2" << life_timer << endl;
+  return life_timer;
 }
 
+// end AIBallistic