#include "AIBallistic.hxx"
+
FGAIBallistic::FGAIBallistic(FGAIManager* mgr) {
manager = mgr;
_type_str = "ballistic";
_otype = otBallistic;
drag_area = 0.007;
+ life_timer = 0.0;
+ gravity = 32;
+// buoyancy = 64;
+ no_roll = false;
}
FGAIBallistic::~FGAIBallistic() {
bool FGAIBallistic::init() {
FGAIBase::init();
- aero_stabilized = true;
+ 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) {
pitch = elevation = el;
}
+void FGAIBallistic::setRoll(double rl) {
+ rotation = rl;
+}
void FGAIBallistic::setStabilization(bool val) {
aero_stabilized = val;
drag_area = a;
}
+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::setWeight(double w) {
+ weight = w;
+}
+
void FGAIBallistic::Run(double dt) {
+ life_timer += dt;
+ 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 mass;
+
+ // the drag calculations below assume sea-level density,
+ // rho = 0.023780 slugs/ft3
+ // calculate mass
+ mass = weight * lbs_to_slugs;
+
+ // drag = Cd * 0.5 * rho * speed * speed * drag_area;
+ // acceleration = drag/mass;
+ // adjust speed by drag
+ speed -= (Cd * 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;
// set destruction flag if altitude less than sea level -1000
if (altitude < -1000.0) setDie(true);
+} // end Run
+
+double FGAIBallistic::_getTime() const {
+ return life_timer;
}
+// end AIBallistic