/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 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" #include "FGPropertyManager.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; vPQRdot.InitMatrix(); vPQRdot_prev[0].InitMatrix(); vPQRdot_prev[1].InitMatrix(); vPQRdot_prev[2].InitMatrix(); bind(); Debug(0); } //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% FGRotation::~FGRotation() { unbind(); 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 += State->Integrate(FGState::TRAPZ, dt*rate, vPQRdot, vPQRdot_prev); 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; } 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(); } //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% void FGRotation::bind(void) { typedef double (FGRotation::*PMF)(int) const; PropertyManager->Tie("velocities/p-rad_sec", this,1, (PMF)&FGRotation::GetPQR); PropertyManager->Tie("velocities/q-rad_sec", this,2, (PMF)&FGRotation::GetPQR); PropertyManager->Tie("velocities/r-rad_sec", this,3, (PMF)&FGRotation::GetPQR); PropertyManager->Tie("velocities/p-aero-rad_sec", this,1, (PMF)&FGRotation::GetAeroPQR); PropertyManager->Tie("velocities/q-aero-rad_sec", this,2, (PMF)&FGRotation::GetAeroPQR); PropertyManager->Tie("velocities/r-aero-rad_sec", this,3, (PMF)&FGRotation::GetAeroPQR); PropertyManager->Tie("accelerations/pdot-rad_sec", this,1, (PMF)&FGRotation::GetPQRdot); PropertyManager->Tie("accelerations/qdot-rad_sec", this,2, (PMF)&FGRotation::GetPQRdot); PropertyManager->Tie("accelerations/rdot-rad_sec", this,3, (PMF)&FGRotation::GetPQRdot); PropertyManager->Tie("attitude/roll-rad", this,1, (PMF)&FGRotation::GetEuler); PropertyManager->Tie("attitude/pitch-rad", this,2, (PMF)&FGRotation::GetEuler); PropertyManager->Tie("attitude/heading-true-rad", this,3, (PMF)&FGRotation::GetEuler); PropertyManager->Tie("velocities/phidot-rad_sec", this,1, (PMF)&FGRotation::GetEulerRates); PropertyManager->Tie("velocities/thetadot-rad_sec", this,2, (PMF)&FGRotation::GetEulerRates); PropertyManager->Tie("velocities/psidot-rad_sec", this,3, (PMF)&FGRotation::GetEulerRates); PropertyManager->Tie("attitude/phi-rad", this, &FGRotation::Getphi); PropertyManager->Tie("attitude/theta-rad", this, &FGRotation::Gettht); PropertyManager->Tie("attitude/psi-true-rad", this, &FGRotation::Getpsi); } //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% void FGRotation::unbind(void) { PropertyManager->Untie("velocities/p-rad_sec"); PropertyManager->Untie("velocities/q-rad_sec"); PropertyManager->Untie("velocities/r-rad_sec"); PropertyManager->Untie("velocities/p-aero-rad_sec"); PropertyManager->Untie("velocities/q-aero-rad_sec"); PropertyManager->Untie("velocities/r-aero-rad_sec"); PropertyManager->Untie("accelerations/pdot-rad_sec"); PropertyManager->Untie("accelerations/qdot-rad_sec"); PropertyManager->Untie("accelerations/rdot-rad_sec"); PropertyManager->Untie("attitude/roll-rad"); PropertyManager->Untie("attitude/pitch-rad"); PropertyManager->Untie("attitude/heading-true-rad"); PropertyManager->Untie("velocities/phidot-rad_sec"); PropertyManager->Untie("velocities/thetadot-rad_sec"); PropertyManager->Untie("velocities/psidot-rad_sec"); PropertyManager->Untie("attitude/phi-rad"); PropertyManager->Untie("attitude/theta-rad"); PropertyManager->Untie("attitude/psi-true-rad"); } //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% // 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; } } if (debug_lvl & 64) { if (from == 0) { // Constructor cout << IdSrc << endl; cout << IdHdr << endl; } } }