#include <stdio.h>
+#include <cstring>
+#include <cstdlib>
+
#include <simgear/props/props.hxx>
#include <simgear/xml/easyxml.hxx>
#include "FGFDM.hpp"
+#include "Atmosphere.hpp"
#include "Airplane.hpp"
+#include <simgear/math/SGMath.hxx>
+
using namespace yasim;
// Stubs. Not needed by a batch program, but required to link.
bool fgSetFloat (const char * name, float val) { return false; }
bool fgSetBool(char const * name, bool val) { return false; }
bool fgGetBool(char const * name, bool def) { return false; }
+bool fgSetString(char const * name, char const * str) { return false; }
SGPropertyNode* fgGetNode (const char * path, bool create) { return 0; }
+SGPropertyNode* fgGetNode (const char * path, int i, bool create) { return 0; }
float fgGetFloat (const char * name, float defaultValue) { return 0; }
-float fgGetDouble (const char * name, double defaultValue) { return 0; }
-float fgSetDouble (const char * name, double defaultValue) { return 0; }
+double fgGetDouble (const char * name, double defaultValue = 0.0) { return 0; }
+bool fgSetDouble (const char * name, double defaultValue = 0.0) { return 0; }
static const float RAD2DEG = 57.2957795131;
+static const float DEG2RAD = 0.0174532925199;
+static const float KTS2MPS = 0.514444444444;
+
+
+// Generate a graph of lift, drag and L/D against AoA at the specified
+// speed and altitude. The result is a space-separated file of
+// numbers: "aoa lift drag LD" (aoa in degrees, lift and drag in
+// G's). You can use this in gnuplot like so (assuming the output is
+// in a file named "dat":
+/*
+ plot "dat" using 1:2 with lines title 'lift', \
+ "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)
+{
+ Model* m = a->getModel();
+ State s;
+
+ m->setAir(Atmosphere::getStdPressure(alt),
+ Atmosphere::getStdTemperature(alt),
+ Atmosphere::getStdDensity(alt));
+ m->getBody()->recalc();
+
+ for(int deg=-179; deg<=179; deg++) {
+ float aoa = deg * DEG2RAD;
+ 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);
+ float lift = 1 + acc[2] * (1/9.8);
+
+ printf("%d %g %g %g\n", deg, lift, drag, lift/drag);
+ }
+}
+
+int usage()
+{
+ fprintf(stderr, "Usage: yasim <ac.xml> [-g [-a alt] [-s kts]]\n");
+ return 1;
+}
int main(int argc, char** argv)
{
- FGFDM fdm;
- Airplane* a = fdm.getAirplane();
+ FGFDM* fdm = new FGFDM();
+ Airplane* a = fdm->getAirplane();
+
+ if(argc < 2) return usage();
// Read
try {
- readXML(argv[1], fdm);
+ string file = argv[1];
+ readXML(file, *fdm);
} catch (const sg_exception &e) {
printf("XML parse error: %s (%s)\n",
- e.getFormattedMessage().c_str(), e.getOrigin().c_str());
+ e.getFormattedMessage().c_str(), e.getOrigin());
}
// ... and run
a->compile();
-
- float aoa = a->getCruiseAoA() * RAD2DEG;
- float tail = -1 * a->getTailIncidence() * RAD2DEG;
- float drag = 1000 * a->getDragCoefficient();
- float cg[3];
- a->getModel()->getBody()->getCG(cg);
-
- printf("Solution results:");
- printf(" Iterations: %d\n", a->getSolutionIterations());
- printf(" Drag Coefficient: %f\n", drag);
- printf(" Lift Ratio: %f\n", a->getLiftRatio());
- printf(" Cruise AoA: %f\n", aoa);
- printf(" Tail Incidence: %f\n", tail);
- printf("Approach Elevator: %f\n", a->getApproachElevator());
- printf(" CG: %.3f, %.3f, %.3f\n", cg[0], cg[1], cg[2]);
-
if(a->getFailureMsg())
printf("SOLUTION FAILURE: %s\n", a->getFailureMsg());
+
+ if(!a->getFailureMsg() && argc > 2 && strcmp(argv[2], "-g") == 0) {
+ float alt = 5000, kts = 100;
+ for(int i=3; i<argc; i++) {
+ if (std::strcmp(argv[i], "-a") == 0) alt = std::atof(argv[++i]);
+ else if(std::strcmp(argv[i], "-s") == 0) kts = std::atof(argv[++i]);
+ else return usage();
+ }
+ yasim_graph(a, alt, kts);
+ } else {
+ float aoa = a->getCruiseAoA() * RAD2DEG;
+ float tail = -1 * a->getTailIncidence() * RAD2DEG;
+ float drag = 1000 * a->getDragCoefficient();
+ float cg[3];
+ a->getModel()->getBody()->getCG(cg);
+ a->getModel()->getBody()->recalc();
+
+ float SI_inertia[9];
+ a->getModel()->getBody()->getInertiaMatrix(SI_inertia);
+
+ printf("Solution results:");
+ printf(" Iterations: %d\n", a->getSolutionIterations());
+ printf(" Drag Coefficient: %f\n", drag);
+ printf(" Lift Ratio: %f\n", a->getLiftRatio());
+ printf(" Cruise AoA: %f\n", aoa);
+ printf(" Tail Incidence: %f\n", tail);
+ printf("Approach Elevator: %f\n", a->getApproachElevator());
+ printf(" CG: x:%.3f, y:%.3f, z:%.3f\n\n", cg[0], cg[1], cg[2]);
+ printf(" Inertia tensor : %.3f, %.3f, %.3f\n", SI_inertia[0], SI_inertia[1], SI_inertia[2]);
+ printf(" [kg*m^2] %.3f, %.3f, %.3f\n", SI_inertia[3], SI_inertia[4], SI_inertia[5]);
+ printf(" Origo at CG %.3f, %.3f, %.3f\n", SI_inertia[6], SI_inertia[7], SI_inertia[8]);
+ }
+ delete fdm;
+ return 0;
}