#include "FGAuxiliary.h"
#include "FGOutput.h"
-#ifndef M_PI
-/* get a definition for pi */
-#include <simgear/constants.h>
-#define M_PI FG_PI
-#endif
-
/*******************************************************************************
************************************ CODE **************************************
*******************************************************************************/
-FGRotation::FGRotation(FGFDMExec* fdmex) : FGModel(fdmex)
+FGRotation::FGRotation(FGFDMExec* fdmex) : FGModel(fdmex),
+ vPQR(3),
+ vPQRdot(3),
+ vEuler(3),
+ vEulerRates(3),
+ vMoments(3)
{
- Name = "FGRotation";
- Q0dot = Q1dot = Q2dot = Q3dot = 0.0;
- Pdot = Qdot = Rdot = 0.0;
+ Name = "FGRotation";
+ cTht=cPhi=cPsi=1.0;
+ sTht=sPhi=sPsi=0.0;
}
+/******************************************************************************/
FGRotation::~FGRotation(void)
{
}
+/******************************************************************************/
bool FGRotation::Run(void)
{
- float L2, N1, iQtot, sum;
-
- if (!FGModel::Run()) {
- GetState();
-
- lastPdot = Pdot;
- lastQdot = Qdot;
- lastRdot = Rdot;
-
- L2 = L + Ixz*P*Q - (Izz-Iyy)*R*Q;
- N1 = N - (Iyy-Ixx)*P*Q - Ixz*R*Q;
-
- Pdot = (L2*Izz - N1*Ixz) / (Ixx*Izz - Ixz*Ixz);
- Qdot = (M - (Ixx-Izz)*P*R - Ixz*(P*P - R*R))/Iyy;
- Rdot = (N1*Ixx + L2*Ixz) / (Ixx*Izz - Ixz*Ixz);
-
- P += dt*rate*(lastPdot + Pdot)/2.0;
- Q += dt*rate*(lastQdot + Qdot)/2.0;
- R += dt*rate*(lastRdot + Rdot)/2.0;
-
- lastQ0dot = Q0dot;
- lastQ1dot = Q1dot;
- lastQ2dot = Q2dot;
- lastQ3dot = Q3dot;
-
- Q0dot = -0.5*(Q1*P + Q2*Q + Q3*R);
- Q1dot = 0.5*(Q0*P + Q2*R - Q3*Q);
- Q2dot = 0.5*(Q0*Q + Q3*P - Q1*R);
- Q3dot = 0.5*(Q0*R + Q1*Q - Q2*P);
-
- Q0 += 0.5*dt*rate*(lastQ0dot + Q0dot);
- Q1 += 0.5*dt*rate*(lastQ1dot + Q1dot);
- Q2 += 0.5*dt*rate*(lastQ2dot + Q2dot);
- Q3 += 0.5*dt*rate*(lastQ3dot + Q3dot);
-
- sum = Q0*Q0 + Q1*Q1 + Q2*Q2 + Q3*Q3;
-
- iQtot = 1.0 / sqrt(sum);
-
- Q0 *= iQtot;
- Q1 *= iQtot;
- Q2 *= iQtot;
- Q3 *= iQtot;
-
- if (T[3][3] == 0)
- phi = 0.0;
- else
- phi = atan2(T[2][3], T[3][3]);
-
- tht = asin(-T[1][3]);
-
- if (T[1][1] == 0.0)
- psi = 0.0;
- else
- psi = atan2(T[1][2], T[1][1]);
-
- if (psi < 0.0) psi += 2*M_PI;
-
- PutState();
- } else {
- }
- return false;
+ float L2, N1;
+ float tTheta;
+ static FGColumnVector vlastPQRdot(3);
+
+ if (!FGModel::Run()) {
+ GetState();
+
+ L2 = vMoments(eL) + Ixz*vPQR(eP)*vPQR(eQ) - (Izz-Iyy)*vPQR(eR)*vPQR(eQ);
+ N1 = vMoments(eN) - (Iyy-Ixx)*vPQR(eP)*vPQR(eQ) - Ixz*vPQR(eR)*vPQR(eQ);
+
+ vPQRdot(eP) = (L2*Izz - N1*Ixz) / (Ixx*Izz - Ixz*Ixz);
+ vPQRdot(eQ) = (vMoments(eM) - (Ixx-Izz)*vPQR(eP)*vPQR(eR) - Ixz*(vPQR(eP)*vPQR(eP) - vPQR(eR)*vPQR(eR)))/Iyy;
+ vPQRdot(eR) = (N1*Ixx + L2*Ixz) / (Ixx*Izz - Ixz*Ixz);
+
+ vPQR += dt*rate*(vlastPQRdot + vPQRdot)/2.0;
+
+ State->IntegrateQuat(vPQR, rate);
+ State->CalcMatrices();
+ vEuler = State->CalcEuler();
+
+
+ cTht=cos(vEuler(eTht)); sTht=sin(vEuler(eTht));
+ cPhi=cos(vEuler(ePhi)); sPhi=sin(vEuler(ePhi));
+ cPsi=cos(vEuler(ePsi)); sPsi=sin(vEuler(ePsi));
+
+
+ vEulerRates(eTht) = vPQR(2)*cPhi - vPQR(3)*sPhi;
+ if(cTht != 0.0) {
+ tTheta=sTht/cTht; // what's cheaper: / or tan() ?
+ vEulerRates(ePhi) = vPQR(1) + (vPQR(2)*sPhi + vPQR(3)*cPhi)*tTheta;
+ vEulerRates(ePsi) = (vPQR(2)*sPhi + vPQR(3)*cPhi)/cTht;
+ }
+
+ vlastPQRdot = vPQRdot;
+
+ } else {
+ }
+ return false;
}
+/******************************************************************************/
void FGRotation::GetState(void)
{
- dt = State->Getdt();
-
- L = Aircraft->GetL();
- M = Aircraft->GetM();
- N = Aircraft->GetN();
+ dt = State->Getdt();
- Ixx = Aircraft->GetIxx();
- Iyy = Aircraft->GetIyy();
- Izz = Aircraft->GetIzz();
- Ixz = Aircraft->GetIxz();
+ vMoments = Aircraft->GetMoments();
- for (int r=1;r<=3;r++)
- for (int c=1;c<=3;c++)
- T[r][c] = Position->GetT(r,c);
+ Ixx = Aircraft->GetIxx();
+ Iyy = Aircraft->GetIyy();
+ Izz = Aircraft->GetIzz();
+ Ixz = Aircraft->GetIxz();
}
-
-void FGRotation::PutState(void)
-{
-}
+/******************************************************************************/