fly/flightgear
1
0
Fork 0
Code Activity

Attempt to shore up the numerical stability of the AI aircraft movement

Browse source 
computations.  This is probably not needed, but use double's consistently.
This commit is contained in:
curt 2006-07-27 02:27:43 +00:00
parent 1c2a3cc5ac
commit 5fc834f7f5
1 changed files with 21 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

31
src/AIModel/AIAircraft.cxx
View file

@ -233,27 +233,36 @@ void FGAIAircraft::Run(double dt) {
} else {
speed_diff = groundTargetSpeed - speed;
}
if (fabs(speed_diff) > 0.2) {
if (speed_diff > 0.0)
speed += performance->accel * dt;
if (speed_diff < 0.0) {
if (no_roll) { // was (!no_roll) but seems more logical this way (ground brakes).
speed -= performance->decel * dt * 3;
} else {
speed -= performance->decel * dt;
}
if (speed_diff > 0.0) {
speed += performance->accel * dt;
if ( speed > tgt_speed ) speed = tgt_speed; // don't overshoot
} else if (speed_diff < 0.0) {
if (no_roll) {
// on ground (aircraft can't roll)
speed -= performance->decel * dt * 3;
} else {
speed -= performance->decel * dt;
}
if ( speed < tgt_speed ) speed = tgt_speed; // don't overshoot
}
// convert speed to degrees per second
speed_north_deg_sec = cos( hdg / SG_RADIANS_TO_DEGREES )
speed_north_deg_sec = cos( hdg * SGD_DEGREES_TO_RADIANS )
* speed * 1.686 / ft_per_deg_lat;
speed_east_deg_sec = sin( hdg / SG_RADIANS_TO_DEGREES )
speed_east_deg_sec = sin( hdg * SGD_DEGREES_TO_RADIANS )
* speed * 1.686 / ft_per_deg_lon;
// set new position
pos.setLatitudeDeg( pos.getLatitudeDeg() + speed_north_deg_sec * dt);
pos.setLongitudeDeg( pos.getLongitudeDeg() + speed_east_deg_sec * dt);
/* printf("%.7f %0.4f %.7f %.5f %.7f %.7f %.8f %.8f %.9f %.9f\n",
dt, hdg, speed, ft_per_deg_lat,
cos( hdg * SGD_DEGREES_TO_RADIANS ),
speed * 1.686 / ft_per_deg_lat,
speed_north_deg_sec, speed_east_deg_sec,
pos.getLatitudeDeg(), pos.getLongitudeDeg()); */
//if (!(finite(pos.lat()) && finite(pos.lon())))
// {
// cerr << "Position is not finite" << endl;