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YASIM type name clarification

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This commit is contained in:
Henning Stahlke 2017-12-13 19:15:49 +01:00
parent 13e00b275b
commit e913e44aa0
2 changed files with 135 additions and 135 deletions
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266
src/FDM/YASim/Airplane.cpp
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@ -60,9 +60,9 @@ Airplane::~Airplane()
for(i=0; i<_solveWeights.size(); i++)
delete (SolveWeight*)_solveWeights.get(i);
for(i=0; i<_cruiseConfig.controls.size(); i++)
delete (Control*)_cruiseConfig.controls.get(i);
delete (ControlSetting*)_cruiseConfig.controls.get(i);
for(i=0; i<_approachConfig.controls.size(); i++) {
Control* c = (Control*)_approachConfig.controls.get(i);
ControlSetting* c = (ControlSetting*)_approachConfig.controls.get(i);
if(c != &_approachElevator)
delete c;
}
@ -152,19 +152,19 @@ void Airplane::setElevatorControl(int control)
void Airplane::addApproachControl(int control, float val)
{
Control* c = new Control();
ControlSetting* c = new ControlSetting();
c->control = control;
c->val = val;
_approachConfig.controls.add(c);
_approachConfig.controls.add(c);
}
void Airplane::addCruiseControl(int control, float val)
{
Control* c = new Control();
ControlSetting* c = new ControlSetting();
c->control = control;
c->val = val;
_cruiseConfig.controls.add(c);
}
_cruiseConfig.controls.add(c);
}
void Airplane::addSolutionWeight(bool approach, int idx, float wgt)
{
@ -258,11 +258,11 @@ void Airplane::setWeight(int handle, float mass)
// how we simulate droppable stores.
if(mass == 0) {
wr->surf->setXDrag(0);
wr->surf->setYDrag(0);
wr->surf->setYDrag(0);
wr->surf->setZDrag(0);
} else {
wr->surf->setXDrag(1);
wr->surf->setYDrag(1);
wr->surf->setYDrag(1);
wr->surf->setZDrag(1);
}
}
@ -331,7 +331,7 @@ float Airplane::compileFuselage(Fuselage* f)
float len = Math::mag3(fwd);
if (len == 0) {
_failureMsg = "Zero length fuselage";
return 0;
return 0;
}
float wid = f->width;
int segs = (int)Math::ceil(len/wid);
@ -344,14 +344,14 @@ float Airplane::compileFuselage(Fuselage* f)
if(frac < f->mid)
scale = f->taper+(1-f->taper) * (frac / f->mid);
else {
if( isVersionOrNewer( YASIM_VERSION_32 ) ) {
// Correct calculation of width for fuselage taper.
scale = 1 - (1-f->taper) * (frac - f->mid) / (1 - f->mid);
} else {
// Original, incorrect calculation of width for fuselage taper.
scale = f->taper+(1-f->taper) * (frac - f->mid) / (1 - f->mid);
}
}
if( isVersionOrNewer( YASIM_VERSION_32 ) ) {
// Correct calculation of width for fuselage taper.
scale = 1 - (1-f->taper) * (frac - f->mid) / (1 - f->mid);
} else {
// Original, incorrect calculation of width for fuselage taper.
scale = f->taper+(1-f->taper) * (frac - f->mid) / (1 - f->mid);
}
}
// Where are we?
float pos[3];
@ -367,40 +367,40 @@ float Airplane::compileFuselage(Fuselage* f)
Surface* s = new Surface(this);
s->setPosition(pos);
// The following is the original YASim value for sideDrag.
// Originally YASim calculated the fuselage's lateral drag
// coefficient as (solver drag factor) * (len/wid).
// However, this greatly underestimates a fuselage's lateral drag.
float sideDrag = len/wid;
// The following is the original YASim value for sideDrag.
// Originally YASim calculated the fuselage's lateral drag
// coefficient as (solver drag factor) * (len/wid).
// However, this greatly underestimates a fuselage's lateral drag.
float sideDrag = len/wid;
if ( isVersionOrNewer( YASIM_VERSION_32 ) ) {
// New YASim assumes a fixed lateral drag coefficient of 0.5.
// This will not be multiplied by the solver drag factor, because
// that factor is tuned to match the drag in the direction of
// flight, which is completely independent of lateral drag.
// The value of 0.5 is only a ballpark estimate, roughly matching
// the side-on drag for a long cylinder at the higher Reynolds
// numbers typical for an aircraft's lateral drag.
// This fits if the fuselage is long and has a round cross section.
// For flat-sided fuselages, the value should be increased, up to
// a limit of around 2 for a long rectangular prism.
// For very short fuselages, in which the end effects are strong,
// the value should be reduced.
// Such adjustments can be made using the fuselage's "cy" and "cz"
// XML parameters: "cy" for the sides, "cz" for top and bottom.
sideDrag = 0.5;
}
if ( isVersionOrNewer( YASIM_VERSION_32 ) ) {
// New YASim assumes a fixed lateral drag coefficient of 0.5.
// This will not be multiplied by the solver drag factor, because
// that factor is tuned to match the drag in the direction of
// flight, which is completely independent of lateral drag.
// The value of 0.5 is only a ballpark estimate, roughly matching
// the side-on drag for a long cylinder at the higher Reynolds
// numbers typical for an aircraft's lateral drag.
// This fits if the fuselage is long and has a round cross section.
// For flat-sided fuselages, the value should be increased, up to
// a limit of around 2 for a long rectangular prism.
// For very short fuselages, in which the end effects are strong,
// the value should be reduced.
// Such adjustments can be made using the fuselage's "cy" and "cz"
// XML parameters: "cy" for the sides, "cz" for top and bottom.
sideDrag = 0.5;
}
if( isVersionOrNewer( YASIM_VERSION_32 ) ) {
if( isVersionOrNewer( YASIM_VERSION_32 ) ) {
s->setXDrag(f->_cx);
}
}
s->setYDrag(sideDrag*f->_cy);
s->setZDrag(sideDrag*f->_cz);
if( isVersionOrNewer( YASIM_VERSION_32 ) ) {
if( isVersionOrNewer( YASIM_VERSION_32 ) ) {
s->setDragCoefficient(scale*segWgt);
} else {
s->setDragCoefficient(scale*segWgt*f->_cx);
}
}
s->setInducedDrag(f->_idrag);
// FIXME: fails for fuselages aligned along the Y axis
@ -409,8 +409,8 @@ float Airplane::compileFuselage(Fuselage* f)
Math::unit3(fwd, x);
y[0] = 0; y[1] = 1; y[2] = 0;
Math::cross3(x, y, z);
Math::unit3(z, z);
Math::cross3(z, x, y);
Math::unit3(z, z);
Math::cross3(z, x, y);
s->setOrientation(o);
_model.addSurface(s);
@ -503,38 +503,38 @@ void Airplane::compile()
// The Wing objects
if (_wing)
{
if (baseN != 0) {
_wingsN = baseN->getChild("wing", 0, true);
_wing->setPropertyNode(_wingsN);
}
aeroWgt += compileWing(_wing);
// convert % to absolute x coordinates
_cgDesiredFront = _wing->getMACx() - _wing->getMACLength()*_cgDesiredMin;
_cgDesiredAft = _wing->getMACx() - _wing->getMACLength()*_cgDesiredMax;
if (baseN != 0) {
SGPropertyNode_ptr n = fgGetNode("/fdm/yasim/model", true);
n->getNode("cg-x-range-front", true)->setFloatValue(_cgDesiredFront);
n->getNode("cg-x-range-aft", true)->setFloatValue(_cgDesiredAft);
}
if (baseN != 0) {
_wingsN = baseN->getChild("wing", 0, true);
_wing->setPropertyNode(_wingsN);
}
aeroWgt += compileWing(_wing);
// convert % to absolute x coordinates
_cgDesiredFront = _wing->getMACx() - _wing->getMACLength()*_cgDesiredMin;
_cgDesiredAft = _wing->getMACx() - _wing->getMACLength()*_cgDesiredMax;
if (baseN != 0) {
SGPropertyNode_ptr n = fgGetNode("/fdm/yasim/model", true);
n->getNode("cg-x-range-front", true)->setFloatValue(_cgDesiredFront);
n->getNode("cg-x-range-aft", true)->setFloatValue(_cgDesiredAft);
}
}
if (_tail)
{
if (baseN != 0) {
_wingsN = baseN->getChild("tail", 0, true);
_tail->setPropertyNode(_wingsN);
}
aeroWgt += compileWing(_tail);
if (baseN != 0) {
_wingsN = baseN->getChild("tail", 0, true);
_tail->setPropertyNode(_wingsN);
}
aeroWgt += compileWing(_tail);
}
int i;
for(i=0; i<_vstabs.size(); i++)
{
Wing* vs = (Wing*)_vstabs.get(i);
if (baseN != 0) {
_wingsN = baseN->getChild("stab", i, true);
vs->setPropertyNode(_wingsN);
}
aeroWgt += compileWing(vs);
Wing* vs = (Wing*)_vstabs.get(i);
if (baseN != 0) {
_wingsN = baseN->getChild("stab", i, true);
vs->setPropertyNode(_wingsN);
}
aeroWgt += compileWing(vs);
}
// The fuselage(s)
@ -718,12 +718,12 @@ void Airplane::setupWeights(bool isApproach)
/// load values for controls as defined in cruise configuration
void Airplane::loadControls(const Vector& controls)
{
_controls.reset();
for(int i=0; i < controls.size(); i++) {
Control* c = (Control*)controls.get(i);
_controls.reset();
for(int i=0; i < controls.size(); i++) {
ControlSetting* c = (ControlSetting*)controls.get(i);
_controls.setInput(c->control, c->val);
}
_controls.applyControls();
}
_controls.applyControls();
}
/// Helper for solve()
@ -801,11 +801,11 @@ void Airplane::applyDragFactor(float factor)
}
}
for(i=0; i<_weights.size(); i++) {
WeightRec* wr = (WeightRec*)_weights.get(i);
WeightRec* wr = (WeightRec*)_weights.get(i);
wr->surf->setDragCoefficient(wr->surf->getDragCoefficient() * applied);
}
for(i=0; i<_gears.size(); i++) {
GearRec* gr = (GearRec*)_gears.get(i);
GearRec* gr = (GearRec*)_gears.get(i);
gr->surf->setDragCoefficient(gr->surf->getDragCoefficient() * applied);
}
}
@ -848,57 +848,57 @@ void Airplane::solve()
return;
}
// Run an iteration at cruise, and extract the needed numbers:
runConfig(_cruiseConfig);
// Run an iteration at cruise, and extract the needed numbers:
runConfig(_cruiseConfig);
_model.getThrust(tmp);
_model.getThrust(tmp);
float thrust = tmp[0] + _cruiseConfig.weight * Math::sin(_cruiseConfig.glideAngle) * 9.81;
_model.getBody()->getAccel(tmp);
_model.getBody()->getAccel(tmp);
_cruiseConfig.state.localToGlobal(tmp, tmp);
float xforce = _cruiseConfig.weight * tmp[0];
float clift0 = _cruiseConfig.weight * tmp[2];
float xforce = _cruiseConfig.weight * tmp[0];
float clift0 = _cruiseConfig.weight * tmp[2];
_model.getBody()->getAngularAccel(tmp);
_model.getBody()->getAngularAccel(tmp);
_cruiseConfig.state.localToGlobal(tmp, tmp);
float pitch0 = tmp[1];
float pitch0 = tmp[1];
// Run an approach iteration, and do likewise
// Run an approach iteration, and do likewise
runConfig(_approachConfig);
_model.getBody()->getAngularAccel(tmp);
_model.getBody()->getAngularAccel(tmp);
_approachConfig.state.localToGlobal(tmp, tmp);
double apitch0 = tmp[1];
double apitch0 = tmp[1];
_model.getBody()->getAccel(tmp);
_model.getBody()->getAccel(tmp);
_approachConfig.state.localToGlobal(tmp, tmp);
float alift = _approachConfig.weight * tmp[2];
float alift = _approachConfig.weight * tmp[2];
// Modify the cruise AoA a bit to get a derivative
_cruiseConfig.aoa += ARCMIN;
// Modify the cruise AoA a bit to get a derivative
_cruiseConfig.aoa += ARCMIN;
runConfig(_cruiseConfig);
_cruiseConfig.aoa -= ARCMIN;
_model.getBody()->getAccel(tmp);
_model.getBody()->getAccel(tmp);
_cruiseConfig.state.localToGlobal(tmp, tmp);
float clift1 = _cruiseConfig.weight * tmp[2];
float clift1 = _cruiseConfig.weight * tmp[2];
// Do the same with the tail incidence
_tail->setIncidence(_tailIncidence + ARCMIN);
// Do the same with the tail incidence
_tail->setIncidence(_tailIncidence + ARCMIN);
runConfig(_cruiseConfig);
_tail->setIncidence(_tailIncidence);
_model.getBody()->getAngularAccel(tmp);
_model.getBody()->getAngularAccel(tmp);
_cruiseConfig.state.localToGlobal(tmp, tmp);
float pitch1 = tmp[1];
float pitch1 = tmp[1];
// Now calculate:
float awgt = 9.8f * _approachConfig.weight;
// Now calculate:
float awgt = 9.8f * _approachConfig.weight;
float dragFactor = thrust / (thrust-xforce);
float liftFactor = awgt / (awgt+alift);
float aoaDelta = -clift0 * (ARCMIN/(clift1-clift0));
float tailDelta = -pitch0 * (ARCMIN/(pitch1-pitch0));
float dragFactor = thrust / (thrust-xforce);
float liftFactor = awgt / (awgt+alift);
float aoaDelta = -clift0 * (ARCMIN/(clift1-clift0));
float tailDelta = -pitch0 * (ARCMIN/(pitch1-pitch0));
// Sanity:
if(dragFactor <= 0 || liftFactor <= 0)
@ -913,36 +913,36 @@ void Airplane::solve()
runConfig(_approachConfig);
_approachElevator.val -= ELEVDIDDLE;
_model.getBody()->getAngularAccel(tmp);
_model.getBody()->getAngularAccel(tmp);
_approachConfig.state.localToGlobal(tmp, tmp);
double apitch1 = tmp[1];
double apitch1 = tmp[1];
float elevDelta = -apitch0 * (ELEVDIDDLE/(apitch1-apitch0));
// Now apply the values we just computed. Note that the
// "minor" variables are deferred until we get the lift/drag
// numbers in the right ballpark.
applyDragFactor(dragFactor);
applyLiftRatio(liftFactor);
applyDragFactor(dragFactor);
applyLiftRatio(liftFactor);
// DON'T do the following until the above are sane
if(normFactor(dragFactor) > STHRESH*1.0001
|| normFactor(liftFactor) > STHRESH*1.0001)
{
continue;
}
// DON'T do the following until the above are sane
if(normFactor(dragFactor) > STHRESH*1.0001
|| normFactor(liftFactor) > STHRESH*1.0001)
{
continue;
}
// OK, now we can adjust the minor variables:
_cruiseConfig.aoa += SOLVE_TWEAK*aoaDelta;
_tailIncidence += SOLVE_TWEAK*tailDelta;
_cruiseConfig.aoa = Math::clamp(_cruiseConfig.aoa, -0.175f, 0.175f);
_tailIncidence = Math::clamp(_tailIncidence, -0.175f, 0.175f);
// OK, now we can adjust the minor variables:
_cruiseConfig.aoa += SOLVE_TWEAK*aoaDelta;
_tailIncidence += SOLVE_TWEAK*tailDelta;
_cruiseConfig.aoa = Math::clamp(_cruiseConfig.aoa, -0.175f, 0.175f);
_tailIncidence = Math::clamp(_tailIncidence, -0.175f, 0.175f);
if(abs(xforce/_cruiseConfig.weight) < STHRESH*0.0001 &&
abs(alift/_approachConfig.weight) < STHRESH*0.0001 &&
abs(aoaDelta) < STHRESH*.000017 &&
abs(tailDelta) < STHRESH*.000017)
abs(alift/_approachConfig.weight) < STHRESH*0.0001 &&
abs(aoaDelta) < STHRESH*.000017 &&
abs(tailDelta) < STHRESH*.000017)
{
// If this finaly value is OK, then we're all done
if(abs(elevDelta) < STHRESH*0.0001)
@ -958,17 +958,17 @@ void Airplane::solve()
}
if(_dragFactor < 1e-06 || _dragFactor > 1e6) {
_failureMsg = "Drag factor beyond reasonable bounds.";
return;
_failureMsg = "Drag factor beyond reasonable bounds.";
return;
} else if(_liftRatio < 1e-04 || _liftRatio > 1e4) {
_failureMsg = "Lift ratio beyond reasonable bounds.";
return;
_failureMsg = "Lift ratio beyond reasonable bounds.";
return;
} else if(Math::abs(_cruiseConfig.aoa) >= .17453293) {
_failureMsg = "Cruise AoA > 10 degrees";
return;
_failureMsg = "Cruise AoA > 10 degrees";
return;
} else if(Math::abs(_tailIncidence) >= .17453293) {
_failureMsg = "Tail incidence > 10 degrees";
return;
_failureMsg = "Tail incidence > 10 degrees";
return;
}
}

4
src/FDM/YASim/Airplane.hpp
View file

@ -134,7 +134,7 @@ private:
float cg[3];
float mass;
};
struct Control {
struct ControlSetting {
int control;
float val;
};
@ -210,7 +210,7 @@ private:
float _dragFactor {1};
float _liftRatio {1};
float _tailIncidence {0};
Control _approachElevator;
ControlSetting _approachElevator;
const char* _failureMsg {0};
float _cgMax {-1e6}; // hard limits for cg from gear position