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YASim CLI tool: add print out of max lift and min drag

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add drag(speed) print function
This commit is contained in:
Henning Stahlke 2017-02-27 09:07:33 +01:00
parent cb7d2a1bc5
commit 1198f5a3ec
1 changed files with 101 additions and 21 deletions
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122
src/FDM/YASim/yasim-test.cpp
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@ -28,6 +28,7 @@ bool fgSetDouble (const char * name, double defaultValue = 0.0) { return 0; }
static const float RAD2DEG = 57.2957795131;
static const float DEG2RAD = 0.0174532925199;
/// knots 2 meters per second
static const float KTS2MPS = 0.514444444444;
@ -48,7 +49,7 @@ enum Config
"dat" using 1:3 with lines title 'drag', \
"dat" using 1:4 with lines title 'LD'
*/
void yasim_graph(Airplane* a, float alt, float kts, int cfg = CONFIG_NONE)
void yasim_graph(Airplane* a, const float alt, const float kts, int cfg = CONFIG_NONE)
{
Model* m = a->getModel();
State s;
@ -69,10 +70,11 @@ void yasim_graph(Airplane* a, float alt, float kts, int cfg = CONFIG_NONE)
}
//if we fake the properties we could also use FGFDM::getExternalInput()
m->getBody()->recalc();
float cl_max = 0, cd_min = 1e6, ld_max = 0;
int cl_max_deg = 0, cd_min_deg = 0, ld_max_deg = 0;
for(int deg=-179; deg<=179; deg++) {
for(int deg=-15; deg<=90; deg++) {
float aoa = deg * DEG2RAD;
Airplane::setupState(aoa, kts * KTS2MPS, 0 ,&s);
m->getBody()->reset();
@ -85,9 +87,25 @@ void yasim_graph(Airplane* a, float alt, float kts, int cfg = CONFIG_NONE)
float drag = acc[0] * (-1/9.8);
float lift = 1 + acc[2] * (1/9.8);
printf("%d %g %g %g\n", deg, lift, drag, lift/drag);
float ld = lift/drag;
if (cd_min > drag) {
cd_min = drag;
cd_min_deg = deg;
}
if (cl_max < lift) {
cl_max = lift;
cl_max_deg = deg;
}
if (ld_max < ld) {
ld_max= ld;
ld_max_deg = deg;
}
printf("%d %g %g %g\n", deg, lift, drag, ld);
}
printf("# cl_max %g at %d deg\n", cl_max, cl_max_deg);
printf("# cd_min %g at %d deg\n", cd_min, cd_min_deg);
printf("# ld_max %g at %d deg\n", ld_max, ld_max_deg);
}
void yasim_masses(Airplane* a)
@ -107,11 +125,60 @@ void yasim_masses(Airplane* a)
printf("Total mass: %g", mass);
}
void yasim_drag(Airplane* a, const float aoa, const float alt, int cfg = CONFIG_NONE)
{
fprintf(stderr,"yasim_drag");
Model* m = a->getModel();
State s;
m->setAir(Atmosphere::getStdPressure(alt),
Atmosphere::getStdTemperature(alt),
Atmosphere::getStdDensity(alt));
switch (cfg) {
case CONFIG_APPROACH:
a->loadApproachControls();
break;
case CONFIG_CRUISE:
a->loadCruiseControls();
break;
case CONFIG_NONE:
break;
}
m->getBody()->recalc();
float cd_min = 1e6;
int cd_min_kts = 0;
printf("#kts, drag\n");
for(int kts=15; kts<=150; kts++) {
Airplane::setupState(aoa, kts * KTS2MPS, 0 ,&s);
m->getBody()->reset();
m->initIteration();
m->calcForces(&s);
float acc[3];
m->getBody()->getAccel(acc);
Math::tmul33(s.orient, acc, acc);
float drag = acc[0] * (-1/9.8);
if (cd_min > drag) {
cd_min = drag;
cd_min_kts = kts;
}
printf("%d %g\n", kts, drag);
}
printf("# cd_min %g at %d kts\n", cd_min, cd_min_kts);
}
int usage()
{
fprintf(stderr, "Usage: yasim <ac.xml> [-g [-a alt] [-s kts] [-approach | -cruise] ]\n");
fprintf(stderr, " yasim <ac.xml> [-d [-a alt] [-approach | -cruise] ]\n");
fprintf(stderr, " yasim <ac.xml> [-m]\n");
fprintf(stderr, " -g print lift/drag table: aoa, lift, drag, lift/drag \n");
fprintf(stderr, " -d print drag over TAS: kts, drag\n");
fprintf(stderr, " -m print mass distribution table: id, x, y, z, mass \n");
return 1;
}
@ -119,24 +186,24 @@ int usage()
int main(int argc, char** argv)
{
FGFDM* fdm = new FGFDM();
Airplane* a = fdm->getAirplane();
FGFDM* fdm = new FGFDM();
Airplane* a = fdm->getAirplane();
if(argc < 2) return usage();
// Read
try {
string file = argv[1];
readXML(SGPath(file), *fdm);
} catch (const sg_exception &e) {
printf("XML parse error: %s (%s)\n",
e.getFormattedMessage().c_str(), e.getOrigin());
}
if(argc < 2) return usage();
// Read
try {
string file = argv[1];
readXML(SGPath(file), *fdm);
}
catch (const sg_exception &e) {
printf("XML parse error: %s (%s)\n", e.getFormattedMessage().c_str(), e.getOrigin());
}
// ... and run
a->compile();
if(a->getFailureMsg())
printf("SOLUTION FAILURE: %s\n", a->getFailureMsg());
if(!a->getFailureMsg() && argc > 2 ) {
// ... and run
a->compile();
if(a->getFailureMsg())
printf("SOLUTION FAILURE: %s\n", a->getFailureMsg());
if(!a->getFailureMsg() && argc > 2 ) {
if(strcmp(argv[2], "-g") == 0) {
float alt = 5000, kts = 100;
int cfg = CONFIG_NONE;
@ -153,6 +220,19 @@ int main(int argc, char** argv)
}
yasim_graph(a, alt, kts, cfg);
}
else if(strcmp(argv[2], "-d") == 0) {
float alt = 2000, aoa = a->getCruiseAoA();
int cfg = CONFIG_NONE;
for(int i=3; i<argc; i++) {
if (std::strcmp(argv[i], "-a") == 0) {
if (i+1 < argc) alt = std::atof(argv[++i]);
}
else if(std::strcmp(argv[i], "-approach") == 0) cfg = CONFIG_APPROACH;
else if(std::strcmp(argv[i], "-cruise") == 0) cfg = CONFIG_CRUISE;
else return usage();
}
yasim_drag(a, aoa, alt, cfg);
}
else if(strcmp(argv[2], "-m") == 0) {
yasim_masses(a);
}