198 lines
6.7 KiB
C++
198 lines
6.7 KiB
C++
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
|
Module: FGRotation.cpp
|
|
Author: Jon Berndt
|
|
Date started: 12/02/98
|
|
Purpose: Integrates the rotational EOM
|
|
Called by: FGFDMExec
|
|
|
|
------------- Copyright (C) 1999 Jon S. Berndt (jsb@hal-pc.org) -------------
|
|
|
|
This program is free software; you can redistribute it and/or modify it under
|
|
the terms of the GNU General Public License as published by the Free Software
|
|
Foundation; either version 2 of the License, or (at your option) any later
|
|
version.
|
|
|
|
This program is distributed in the hope that it will be useful, but WITHOUT
|
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
|
|
details.
|
|
|
|
You should have received a copy of the GNU General Public License along with
|
|
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
|
|
Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
Further information about the GNU General Public License can also be found on
|
|
the world wide web at http://www.gnu.org.
|
|
|
|
FUNCTIONAL DESCRIPTION
|
|
--------------------------------------------------------------------------------
|
|
This class integrates the rotational EOM.
|
|
|
|
HISTORY
|
|
--------------------------------------------------------------------------------
|
|
12/02/98 JSB Created
|
|
|
|
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
COMMENTS, REFERENCES, and NOTES
|
|
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
[1] Cooke, Zyda, Pratt, and McGhee, "NPSNET: Flight Simulation Dynamic Modeling
|
|
Using Quaternions", Presence, Vol. 1, No. 4, pp. 404-420 Naval Postgraduate
|
|
School, January 1994
|
|
[2] D. M. Henderson, "Euler Angles, Quaternions, and Transformation Matrices",
|
|
JSC 12960, July 1977
|
|
[3] Richard E. McFarland, "A Standard Kinematic Model for Flight Simulation at
|
|
NASA-Ames", NASA CR-2497, January 1975
|
|
[4] Barnes W. McCormick, "Aerodynamics, Aeronautics, and Flight Mechanics",
|
|
Wiley & Sons, 1979 ISBN 0-471-03032-5
|
|
[5] Bernard Etkin, "Dynamics of Flight, Stability and Control", Wiley & Sons,
|
|
1982 ISBN 0-471-08936-2
|
|
|
|
The order of rotations used in this class corresponds to a 3-2-1 sequence,
|
|
or Y-P-R, or Z-Y-X, if you prefer.
|
|
|
|
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
INCLUDES
|
|
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
|
|
|
|
#include "FGRotation.h"
|
|
#include "FGAtmosphere.h"
|
|
#include "FGState.h"
|
|
#include "FGFDMExec.h"
|
|
#include "FGFCS.h"
|
|
#include "FGAircraft.h"
|
|
#include "FGMassBalance.h"
|
|
#include "FGTranslation.h"
|
|
#include "FGPosition.h"
|
|
#include "FGAuxiliary.h"
|
|
#include "FGOutput.h"
|
|
|
|
static const char *IdSrc = "$Id$";
|
|
static const char *IdHdr = ID_ROTATION;
|
|
|
|
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
CLASS IMPLEMENTATION
|
|
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
|
|
|
|
|
|
FGRotation::FGRotation(FGFDMExec* fdmex) : FGModel(fdmex)
|
|
{
|
|
Name = "FGRotation";
|
|
cTht=cPhi=cPsi=1.0;
|
|
sTht=sPhi=sPsi=0.0;
|
|
|
|
Debug(0);
|
|
}
|
|
|
|
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
|
FGRotation::~FGRotation()
|
|
{
|
|
Debug(1);
|
|
}
|
|
|
|
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
|
bool FGRotation::Run(void)
|
|
{
|
|
double L2, N1;
|
|
double tTheta;
|
|
|
|
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;
|
|
vAeroPQR = vPQR + Atmosphere->GetTurbPQR();
|
|
|
|
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;
|
|
|
|
if (debug_lvl > 1) Debug(2);
|
|
|
|
return false;
|
|
} else {
|
|
return true;
|
|
}
|
|
}
|
|
|
|
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
|
void FGRotation::GetState(void)
|
|
{
|
|
dt = State->Getdt();
|
|
vMoments = Aircraft->GetMoments();
|
|
|
|
Ixx = MassBalance->GetIxx();
|
|
Iyy = MassBalance->GetIyy();
|
|
Izz = MassBalance->GetIzz();
|
|
Ixz = MassBalance->GetIxz();
|
|
}
|
|
|
|
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
// The bitmasked value choices are as follows:
|
|
// unset: In this case (the default) JSBSim would only print
|
|
// out the normally expected messages, essentially echoing
|
|
// the config files as they are read. If the environment
|
|
// variable is not set, debug_lvl is set to 1 internally
|
|
// 0: This requests JSBSim not to output any messages
|
|
// whatsoever.
|
|
// 1: This value explicity requests the normal JSBSim
|
|
// startup messages
|
|
// 2: This value asks for a message to be printed out when
|
|
// a class is instantiated
|
|
// 4: When this value is set, a message is displayed when a
|
|
// FGModel object executes its Run() method
|
|
// 8: When this value is set, various runtime state variables
|
|
// are printed out periodically
|
|
// 16: When set various parameters are sanity checked and
|
|
// a message is printed out when they go out of bounds
|
|
|
|
void FGRotation::Debug(int from)
|
|
{
|
|
if (debug_lvl <= 0) return;
|
|
|
|
if (debug_lvl & 1) { // Standard console startup message output
|
|
if (from == 0) { // Constructor
|
|
|
|
}
|
|
}
|
|
if (debug_lvl & 2 ) { // Instantiation/Destruction notification
|
|
if (from == 0) cout << "Instantiated: FGRotation" << endl;
|
|
if (from == 1) cout << "Destroyed: FGRotation" << endl;
|
|
}
|
|
if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
|
|
}
|
|
if (debug_lvl & 8 ) { // Runtime state variables
|
|
}
|
|
if (debug_lvl & 16) { // Sanity check variables
|
|
if (from == 2) {
|
|
if (fabs(vPQR(eP)) > 100)
|
|
cout << "FGRotation::P (Roll Rate) out of bounds: " << vPQR(eP) << endl;
|
|
if (fabs(vPQR(eQ)) > 100)
|
|
cout << "FGRotation::Q (Pitch Rate) out of bounds: " << vPQR(eQ) << endl;
|
|
if (fabs(vPQR(eR)) > 100)
|
|
cout << "FGRotation::R (Yaw Rate) out of bounds: " << vPQR(eR) << endl;
|
|
}
|
|
}
|
|
}
|