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

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

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