src/FDM/JSBSim/models/atmosphere/FGWinds.cpp

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Module:       FGWinds.cpp
   4  Author:       Jon Berndt, Tony Peden, Andreas Gaeb
   5  Date started: Extracted from FGAtmosphere, which originated in 1998
   6                5/2011
   7  Purpose:      Models winds, gusts, turbulence, and other atmospheric disturbances
   8  Called by:    FGFDMExec
   9
  10  ------------- Copyright (C) 2011  Jon S. Berndt (jon@jsbsim.org) -------------
  11
  12  This program is free software; you can redistribute it and/or modify it under
  13  the terms of the GNU Lesser General Public License as published by the Free Software
  14  Foundation; either version 2 of the License, or (at your option) any later
  15  version.
  16
  17  This program is distributed in the hope that it will be useful, but WITHOUT
  18  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  19  FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
  20  details.
  21
  22  You should have received a copy of the GNU Lesser General Public License along with
  23  this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  24  Place - Suite 330, Boston, MA  02111-1307, USA.
  25
  26  Further information about the GNU Lesser General Public License can also be found on
  27  the world wide web at http://www.gnu.org.
  28
  29 FUNCTIONAL DESCRIPTION
  30 --------------------------------------------------------------------------------
  31
  32 HISTORY
  33 --------------------------------------------------------------------------------
  34
  35 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  36 COMMENTS, REFERENCES,  and NOTES
  37 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  38 [1]   Anderson, John D. "Introduction to Flight, Third Edition", McGraw-Hill,
  39       1989, ISBN 0-07-001641-0
  40
  41 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  42 INCLUDES
  43 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  44
  45 #include <iostream>
  46 #include <cstdlib>
  47 #include "FGWinds.h"
  48 #include "FGFDMExec.h"
  49
  50 using namespace std;
  51
  52 namespace JSBSim {
  53
  54 static const char *IdSrc = "$Id: FGWinds.cpp,v 1.5 2011/09/11 11:36:04 bcoconni Exp $";
  55 static const char *IdHdr = ID_WINDS;
  56
  57 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  58 CLASS IMPLEMENTATION
  59 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  60
  61 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  62 // square a value, but preserve the original sign
  63
  64 static inline double square_signed (double value)
  65 {
  66     if (value < 0)
  67         return value * value * -1;
  68     else
  69         return value * value;
  70 }
  71
  72 /// simply square a value
  73 static inline double sqr(double x) { return x*x; }
  74
  75 FGWinds::FGWinds(FGFDMExec* fdmex) : FGModel(fdmex)
  76 {
  77   Name = "FGWinds";
  78
  79   MagnitudedAccelDt = MagnitudeAccel = Magnitude = 0.0;
  80   SetTurbType( ttMilspec );
  81   TurbGain = 1.0;
  82   TurbRate = 10.0;
  83   Rhythmicity = 0.1;
  84   spike = target_time = strength = 0.0;
  85   wind_from_clockwise = 0.0;
  86   psiw = 0.0;
  87
  88   vGustNED.InitMatrix();
  89   vTurbulenceNED.InitMatrix();
  90
  91   // Milspec turbulence model
  92   windspeed_at_20ft = 0.;
  93   probability_of_exceedence_index = 0;
  94   POE_Table = new FGTable(7,12);
  95   // this is Figure 7 from p. 49 of MIL-F-8785C
  96   // rows: probability of exceedance curve index, cols: altitude in ft
  97   *POE_Table
  98            << 500.0 << 1750.0 << 3750.0 << 7500.0 << 15000.0 << 25000.0 << 35000.0 << 45000.0 << 55000.0 << 65000.0 << 75000.0 << 80000.0
  99     << 1   <<   3.2 <<    2.2 <<    1.5 <<    0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0
 100     << 2   <<   4.2 <<    3.6 <<    3.3 <<    1.6 <<     0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0
 101     << 3   <<   6.6 <<    6.9 <<    7.4 <<    6.7 <<     4.6 <<     2.7 <<     0.4 <<     0.0 <<     0.0 <<     0.0 <<     0.0 <<     0.0
 102     << 4   <<   8.6 <<    9.6 <<   10.6 <<   10.1 <<     8.0 <<     6.6 <<     5.0 <<     4.2 <<     2.7 <<     0.0 <<     0.0 <<     0.0
 103     << 5   <<  11.8 <<   13.0 <<   16.0 <<   15.1 <<    11.6 <<     9.7 <<     8.1 <<     8.2 <<     7.9 <<     4.9 <<     3.2 <<     2.1
 104     << 6   <<  15.6 <<   17.6 <<   23.0 <<   23.6 <<    22.1 <<    20.0 <<    16.0 <<    15.1 <<    12.1 <<     7.9 <<     6.2 <<     5.1
 105     << 7   <<  18.7 <<   21.5 <<   28.4 <<   30.2 <<    30.7 <<    31.0 <<    25.2 <<    23.1 <<    17.5 <<    10.7 <<     8.4 <<     7.2;
 106
 107   bind();
 108   Debug(0);
 109 }
 110
 111 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 112
 113 FGWinds::~FGWinds()
 114 {
 115   delete(POE_Table);
 116   Debug(1);
 117 }
 118
 119 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 120
 121 bool FGWinds::InitModel(void)
 122 {
 123   return true;
 124 }
 125
 126 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 127
 128 bool FGWinds::Run(bool Holding)
 129 {
 130   if (FGModel::Run(Holding)) return true;
 131   if (Holding) return false;
 132
 133   RunPreFunctions();
 134
 135   if (turbType != ttNone) Turbulence(in.AltitudeASL);
 136   if (oneMinusCosineGust.gustProfile.Running) CosineGust();
 137
 138   vTotalWindNED = vWindNED + vGustNED + vCosineGust + vTurbulenceNED;
 139
 140    // psiw (Wind heading) is the direction the wind is blowing towards
 141   if (vWindNED(eX) != 0.0) psiw = atan2( vWindNED(eY), vWindNED(eX) );
 142   if (psiw < 0) psiw += 2*M_PI;
 143
 144   RunPostFunctions();
 145
 146   Debug(2);
 147   return false;
 148 }
 149
 150 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 151 //
 152 // psi is the angle that the wind is blowing *towards*
 153
 154 void FGWinds::SetWindspeed(double speed)
 155 {
 156   if (vWindNED.Magnitude() == 0.0) {
 157     psiw = 0.0;
 158     vWindNED(eNorth) = speed;
 159   } else {
 160     vWindNED(eNorth) = speed * cos(psiw);
 161     vWindNED(eEast) = speed * sin(psiw);
 162     vWindNED(eDown) = 0.0;
 163   }
 164 }
 165
 166 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 167
 168 double FGWinds::GetWindspeed(void) const
 169 {
 170   return vWindNED.Magnitude();
 171 }
 172
 173 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 174 //
 175 // psi is the angle that the wind is blowing *towards*
 176
 177 void FGWinds::SetWindPsi(double dir)
 178 {
 179   double mag = GetWindspeed();
 180   psiw = dir;
 181   SetWindspeed(mag);
 182 }
 183
 184 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 185
 186 void FGWinds::Turbulence(double h)
 187 {
 188   switch (turbType) {
 189
 190   case ttCulp: {
 191
 192     vTurbPQR(eP) = wind_from_clockwise;
 193     if (TurbGain == 0.0) return;
 194
 195     // keep the inputs within allowable limts for this model
 196     if (TurbGain < 0.0) TurbGain = 0.0;
 197     if (TurbGain > 1.0) TurbGain = 1.0;
 198     if (TurbRate < 0.0) TurbRate = 0.0;
 199     if (TurbRate > 30.0) TurbRate = 30.0;
 200     if (Rhythmicity < 0.0) Rhythmicity = 0.0;
 201     if (Rhythmicity > 1.0) Rhythmicity = 1.0;
 202
 203     // generate a sine wave corresponding to turbulence rate in hertz
 204     double time = FDMExec->GetSimTime();
 205     double sinewave = sin( time * TurbRate * 6.283185307 );
 206
 207     double random = 0.0;
 208     if (target_time == 0.0) {
 209       strength = random = 1 - 2.0*(double(rand())/double(RAND_MAX));
 210       target_time = time + 0.71 + (random * 0.5);
 211     }
 212     if (time > target_time) {
 213       spike = 1.0;
 214       target_time = 0.0;
 215     }
 216
 217     // max vertical wind speed in fps, corresponds to TurbGain = 1.0
 218     double max_vs = 40;
 219
 220     vTurbulenceNED(1) = vTurbulenceNED(2) = vTurbulenceNED(3) = 0.0;
 221     double delta = strength * max_vs * TurbGain * (1-Rhythmicity) * spike;
 222
 223     // Vertical component of turbulence.
 224     vTurbulenceNED(3) = sinewave * max_vs * TurbGain * Rhythmicity;
 225     vTurbulenceNED(3)+= delta;
 226     if (in.DistanceAGL/in.wingspan < 3.0)
 227         vTurbulenceNED(3) *= in.DistanceAGL/in.wingspan * 0.3333;
 228
 229     // Yaw component of turbulence.
 230     vTurbulenceNED(1) = sin( delta * 3.0 );
 231     vTurbulenceNED(2) = cos( delta * 3.0 );
 232
 233     // Roll component of turbulence. Clockwise vortex causes left roll.
 234     vTurbPQR(eP) += delta * 0.04;
 235
 236     spike = spike * 0.9;
 237     break;
 238   }
 239   case ttMilspec:
 240   case ttTustin: {
 241
 242     // an index of zero means turbulence is disabled
 243     // airspeed occurs as divisor in the code below
 244     if (probability_of_exceedence_index == 0 || in.V == 0) {
 245       vTurbulenceNED(1) = vTurbulenceNED(2) = vTurbulenceNED(3) = 0.0;
 246       vTurbPQR(1) = vTurbPQR(2) = vTurbPQR(3) = 0.0;
 247       return;
 248     }
 249
 250     // Turbulence model according to MIL-F-8785C (Flying Qualities of Piloted Aircraft)
 251     double b_w = in.wingspan, L_u, L_w, sig_u, sig_w;
 252
 253       if (b_w == 0.) b_w = 30.;
 254
 255     // clip height functions at 10 ft
 256     if (h <= 10.) h = 10;
 257
 258     // Scale lengths L and amplitudes sigma as function of height
 259     if (h <= 1000) {
 260       L_u = h/pow(0.177 + 0.000823*h, 1.2); // MIL-F-8785c, Fig. 10, p. 55
 261       L_w = h;
 262       sig_w = 0.1*windspeed_at_20ft;
 263       sig_u = sig_w/pow(0.177 + 0.000823*h, 0.4); // MIL-F-8785c, Fig. 11, p. 56
 264     } else if (h <= 2000) {
 265       // linear interpolation between low altitude and high altitude models
 266       L_u = L_w = 1000 + (h-1000.)/1000.*750.;
 267       sig_u = sig_w = 0.1*windspeed_at_20ft
 268                     + (h-1000.)/1000.*(POE_Table->GetValue(probability_of_exceedence_index, h) - 0.1*windspeed_at_20ft);
 269     } else {
 270       L_u = L_w = 1750.; //  MIL-F-8785c, Sec. 3.7.2.1, p. 48
 271       sig_u = sig_w = POE_Table->GetValue(probability_of_exceedence_index, h);
 272     }
 273
 274     // keep values from last timesteps
 275     // TODO maybe use deque?
 276     static double
 277       xi_u_km1 = 0, nu_u_km1 = 0,
 278       xi_v_km1 = 0, xi_v_km2 = 0, nu_v_km1 = 0, nu_v_km2 = 0,
 279       xi_w_km1 = 0, xi_w_km2 = 0, nu_w_km1 = 0, nu_w_km2 = 0,
 280       xi_p_km1 = 0, nu_p_km1 = 0,
 281       xi_q_km1 = 0, xi_r_km1 = 0;
 282
 283
 284     double
 285       T_V = in.totalDeltaT, // for compatibility of nomenclature
 286       sig_p = 1.9/sqrt(L_w*b_w)*sig_w, // Yeager1998, eq. (8)
 287       //sig_q = sqrt(M_PI/2/L_w/b_w), // eq. (14)
 288       //sig_r = sqrt(2*M_PI/3/L_w/b_w), // eq. (17)
 289       L_p = sqrt(L_w*b_w)/2.6, // eq. (10)
 290       tau_u = L_u/in.V, // eq. (6)
 291       tau_w = L_w/in.V, // eq. (3)
 292       tau_p = L_p/in.V, // eq. (9)
 293       tau_q = 4*b_w/M_PI/in.V, // eq. (13)
 294       tau_r =3*b_w/M_PI/in.V, // eq. (17)
 295       nu_u = GaussianRandomNumber(),
 296       nu_v = GaussianRandomNumber(),
 297       nu_w = GaussianRandomNumber(),
 298       nu_p = GaussianRandomNumber(),
 299       xi_u=0, xi_v=0, xi_w=0, xi_p=0, xi_q=0, xi_r=0;
 300
 301     // values of turbulence NED velocities
 302
 303     if (turbType == ttTustin) {
 304       // the following is the Tustin formulation of Yeager's report
 305       double
 306         omega_w = in.V/L_w, // hidden in nomenclature p. 3
 307         omega_v = in.V/L_u, // this is defined nowhere
 308         C_BL  = 1/tau_u/tan(T_V/2/tau_u), // eq. (19)
 309         C_BLp = 1/tau_p/tan(T_V/2/tau_p), // eq. (22)
 310         C_BLq = 1/tau_q/tan(T_V/2/tau_q), // eq. (24)
 311         C_BLr = 1/tau_r/tan(T_V/2/tau_r); // eq. (26)
 312
 313       // all values calculated so far are strictly positive, except for
 314       // the random numbers nu_*. This means that in the code below, all
 315       // divisors are strictly positive, too, and no floating point
 316       // exception should occur.
 317       xi_u = -(1 - C_BL*tau_u)/(1 + C_BL*tau_u)*xi_u_km1
 318            + sig_u*sqrt(2*tau_u/T_V)/(1 + C_BL*tau_u)*(nu_u + nu_u_km1); // eq. (18)
 319       xi_v = -2*(sqr(omega_v) - sqr(C_BL))/sqr(omega_v + C_BL)*xi_v_km1
 320            - sqr(omega_v - C_BL)/sqr(omega_v + C_BL) * xi_v_km2
 321            + sig_u*sqrt(3*omega_v/T_V)/sqr(omega_v + C_BL)*(
 322                  (C_BL + omega_v/sqrt(3.))*nu_v
 323                + 2/sqrt(3.)*omega_v*nu_v_km1
 324                + (omega_v/sqrt(3.) - C_BL)*nu_v_km2); // eq. (20) for v
 325       xi_w = -2*(sqr(omega_w) - sqr(C_BL))/sqr(omega_w + C_BL)*xi_w_km1
 326            - sqr(omega_w - C_BL)/sqr(omega_w + C_BL) * xi_w_km2
 327            + sig_w*sqrt(3*omega_w/T_V)/sqr(omega_w + C_BL)*(
 328                  (C_BL + omega_w/sqrt(3.))*nu_w
 329                + 2/sqrt(3.)*omega_w*nu_w_km1
 330                + (omega_w/sqrt(3.) - C_BL)*nu_w_km2); // eq. (20) for w
 331       xi_p = -(1 - C_BLp*tau_p)/(1 + C_BLp*tau_p)*xi_p_km1
 332            + sig_p*sqrt(2*tau_p/T_V)/(1 + C_BLp*tau_p) * (nu_p + nu_p_km1); // eq. (21)
 333       xi_q = -(1 - 4*b_w*C_BLq/M_PI/in.V)/(1 + 4*b_w*C_BLq/M_PI/in.V) * xi_q_km1
 334            + C_BLq/in.V/(1 + 4*b_w*C_BLq/M_PI/in.V) * (xi_w - xi_w_km1); // eq. (23)
 335       xi_r = - (1 - 3*b_w*C_BLr/M_PI/in.V)/(1 + 3*b_w*C_BLr/M_PI/in.V) * xi_r_km1
 336            + C_BLr/in.V/(1 + 3*b_w*C_BLr/M_PI/in.V) * (xi_v - xi_v_km1); // eq. (25)
 337
 338     } else if (turbType == ttMilspec) {
 339       // the following is the MIL-STD-1797A formulation
 340       // as cited in Yeager's report
 341       xi_u = (1 - T_V/tau_u)  *xi_u_km1 + sig_u*sqrt(2*T_V/tau_u)*nu_u;  // eq. (30)
 342       xi_v = (1 - 2*T_V/tau_u)*xi_v_km1 + sig_u*sqrt(4*T_V/tau_u)*nu_v;  // eq. (31)
 343       xi_w = (1 - 2*T_V/tau_w)*xi_w_km1 + sig_w*sqrt(4*T_V/tau_w)*nu_w;  // eq. (32)
 344       xi_p = (1 - T_V/tau_p)  *xi_p_km1 + sig_p*sqrt(2*T_V/tau_p)*nu_p;  // eq. (33)
 345       xi_q = (1 - T_V/tau_q)  *xi_q_km1 + M_PI/4/b_w*(xi_w - xi_w_km1);  // eq. (34)
 346       xi_r = (1 - T_V/tau_r)  *xi_r_km1 + M_PI/3/b_w*(xi_v - xi_v_km1);  // eq. (35)
 347     }
 348
 349     // rotate by wind azimuth and assign the velocities
 350     double cospsi = cos(psiw), sinpsi = sin(psiw);
 351     vTurbulenceNED(1) =  cospsi*xi_u + sinpsi*xi_v;
 352     vTurbulenceNED(2) = -sinpsi*xi_u + cospsi*xi_v;
 353     vTurbulenceNED(3) = xi_w;
 354
 355     vTurbPQR(1) =  cospsi*xi_p + sinpsi*xi_q;
 356     vTurbPQR(2) = -sinpsi*xi_p + cospsi*xi_q;
 357     vTurbPQR(3) = xi_r;
 358
 359     // vTurbPQR is in the body fixed frame, not NED
 360     vTurbPQR = in.Tl2b*vTurbPQR;
 361
 362     // hand on the values for the next timestep
 363     xi_u_km1 = xi_u; nu_u_km1 = nu_u;
 364     xi_v_km2 = xi_v_km1; xi_v_km1 = xi_v; nu_v_km2 = nu_v_km1; nu_v_km1 = nu_v;
 365     xi_w_km2 = xi_w_km1; xi_w_km1 = xi_w; nu_w_km2 = nu_w_km1; nu_w_km1 = nu_w;
 366     xi_p_km1 = xi_p; nu_p_km1 = nu_p;
 367     xi_q_km1 = xi_q;
 368     xi_r_km1 = xi_r;
 369
 370   }
 371   default:
 372     break;
 373   }
 374 }
 375
 376 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 377
 378 double FGWinds::CosineGustProfile(double startDuration, double steadyDuration, double endDuration, double elapsedTime)
 379 {
 380   double factor = 0.0;
 381   if (elapsedTime >= 0 && elapsedTime <= startDuration) {
 382     factor = (1.0 - cos(M_PI*elapsedTime/startDuration))/2.0;
 383   } else if (elapsedTime > startDuration && (elapsedTime <= (startDuration + steadyDuration))) {
 384     factor = 1.0;
 385   } else if (elapsedTime > (startDuration + steadyDuration) && elapsedTime <= (startDuration + steadyDuration + endDuration)) {
 386     factor = (1-cos(M_PI*(1-(elapsedTime-(startDuration + steadyDuration))/endDuration)))/2.0;
 387   } else {
 388     factor = 0.0;
 389   }
 390
 391   return factor;
 392 }
 393
 394 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 395
 396 void FGWinds::CosineGust()
 397 {
 398   struct OneMinusCosineProfile& profile = oneMinusCosineGust.gustProfile;
 399
 400   double factor = CosineGustProfile( profile.startupDuration,
 401                                      profile.steadyDuration,
 402                                      profile.endDuration,
 403                                      profile.elapsedTime);
 404   // Normalize the gust wind vector
 405   oneMinusCosineGust.vWind.Normalize();
 406
 407   if (oneMinusCosineGust.vWindTransformed.Magnitude() == 0.0) {
 408     switch (oneMinusCosineGust.gustFrame) {
 409     case gfBody:
 410       oneMinusCosineGust.vWindTransformed = in.Tl2b.Inverse() * oneMinusCosineGust.vWind;
 411       break;
 412     case gfWind:
 413       oneMinusCosineGust.vWindTransformed = in.Tl2b.Inverse() * in.Tw2b * oneMinusCosineGust.vWind;
 414       break;
 415     case gfLocal:
 416       // this is the native frame - and the default.
 417       oneMinusCosineGust.vWindTransformed = oneMinusCosineGust.vWind;
 418       break;
 419     default:
 420       break;
 421     }
 422   }
 423
 424   vCosineGust = factor * oneMinusCosineGust.vWindTransformed * oneMinusCosineGust.magnitude;
 425
 426   profile.elapsedTime += in.totalDeltaT;
 427
 428   if (profile.elapsedTime > (profile.startupDuration + profile.steadyDuration + profile.endDuration)) {
 429     profile.Running = false;
 430     profile.elapsedTime = 0.0;
 431     oneMinusCosineGust.vWindTransformed.InitMatrix(0.0);
 432     vCosineGust.InitMatrix(0);
 433   }
 434 }
 435
 436 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 437
 438 void FGWinds::bind(void)
 439 {
 440   typedef double (FGWinds::*PMF)(int) const;
 441   typedef int (FGWinds::*PMFt)(void) const;
 442   typedef void   (FGWinds::*PMFd)(int,double);
 443   typedef void   (FGWinds::*PMFi)(int);
 444   typedef double (FGWinds::*Ptr)(void) const;
 445
 446   // User-specified steady, constant, wind properties (local navigational/geographic frame: N-E-D)
 447   PropertyManager->Tie("atmosphere/psiw-rad", this, &FGWinds::GetWindPsi, &FGWinds::SetWindPsi);
 448   PropertyManager->Tie("atmosphere/wind-north-fps", this, eNorth, (PMF)&FGWinds::GetWindNED,
 449                                                           (PMFd)&FGWinds::SetWindNED);
 450   PropertyManager->Tie("atmosphere/wind-east-fps",  this, eEast, (PMF)&FGWinds::GetWindNED,
 451                                                           (PMFd)&FGWinds::SetWindNED);
 452   PropertyManager->Tie("atmosphere/wind-down-fps",  this, eDown, (PMF)&FGWinds::GetWindNED,
 453                                                           (PMFd)&FGWinds::SetWindNED);
 454   PropertyManager->Tie("atmosphere/wind-mag-fps", this, &FGWinds::GetWindspeed,
 455                                                         &FGWinds::SetWindspeed);
 456
 457   // User-specifieded gust (local navigational/geographic frame: N-E-D)
 458   PropertyManager->Tie("atmosphere/gust-north-fps", this, eNorth, (PMF)&FGWinds::GetGustNED,
 459                                                           (PMFd)&FGWinds::SetGustNED);
 460   PropertyManager->Tie("atmosphere/gust-east-fps",  this, eEast, (PMF)&FGWinds::GetGustNED,
 461                                                           (PMFd)&FGWinds::SetGustNED);
 462   PropertyManager->Tie("atmosphere/gust-down-fps",  this, eDown, (PMF)&FGWinds::GetGustNED,
 463                                                           (PMFd)&FGWinds::SetGustNED);
 464
 465   // User-specified 1 - cosine gust parameters (in specified frame)
 466   PropertyManager->Tie("atmosphere/cosine-gust/startup-duration-sec", this, (Ptr)0L, &FGWinds::StartupGustDuration);
 467   PropertyManager->Tie("atmosphere/cosine-gust/steady-duration-sec", this, (Ptr)0L, &FGWinds::SteadyGustDuration);
 468   PropertyManager->Tie("atmosphere/cosine-gust/end-duration-sec", this, (Ptr)0L, &FGWinds::EndGustDuration);
 469   PropertyManager->Tie("atmosphere/cosine-gust/magnitude-ft_sec", this, (Ptr)0L, &FGWinds::GustMagnitude);
 470   PropertyManager->Tie("atmosphere/cosine-gust/frame", this, (PMFt)0L, (PMFi)&FGWinds::GustFrame);
 471   PropertyManager->Tie("atmosphere/cosine-gust/X-velocity-ft_sec", this, (Ptr)0L, &FGWinds::GustXComponent);
 472   PropertyManager->Tie("atmosphere/cosine-gust/Y-velocity-ft_sec", this, (Ptr)0L, &FGWinds::GustYComponent);
 473   PropertyManager->Tie("atmosphere/cosine-gust/Z-velocity-ft_sec", this, (Ptr)0L, &FGWinds::GustZComponent);
 474   PropertyManager->Tie("atmosphere/cosine-gust/start", this, (PMFt)0L, (PMFi)&FGWinds::StartGust);
 475
 476   // User-specified turbulence (local navigational/geographic frame: N-E-D)
 477   PropertyManager->Tie("atmosphere/turb-north-fps", this, eNorth, (PMF)&FGWinds::GetTurbNED,
 478                                                           (PMFd)&FGWinds::SetTurbNED);
 479   PropertyManager->Tie("atmosphere/turb-east-fps",  this, eEast, (PMF)&FGWinds::GetTurbNED,
 480                                                           (PMFd)&FGWinds::SetTurbNED);
 481   PropertyManager->Tie("atmosphere/turb-down-fps",  this, eDown, (PMF)&FGWinds::GetTurbNED,
 482                                                           (PMFd)&FGWinds::SetTurbNED);
 483   // Experimental turbulence parameters
 484   PropertyManager->Tie("atmosphere/p-turb-rad_sec", this,1, (PMF)&FGWinds::GetTurbPQR);
 485   PropertyManager->Tie("atmosphere/q-turb-rad_sec", this,2, (PMF)&FGWinds::GetTurbPQR);
 486   PropertyManager->Tie("atmosphere/r-turb-rad_sec", this,3, (PMF)&FGWinds::GetTurbPQR);
 487   PropertyManager->Tie("atmosphere/turb-type", this, (PMFt)&FGWinds::GetTurbType, (PMFi)&FGWinds::SetTurbType);
 488   PropertyManager->Tie("atmosphere/turb-rate", this, &FGWinds::GetTurbRate, &FGWinds::SetTurbRate);
 489   PropertyManager->Tie("atmosphere/turb-gain", this, &FGWinds::GetTurbGain, &FGWinds::SetTurbGain);
 490   PropertyManager->Tie("atmosphere/turb-rhythmicity", this, &FGWinds::GetRhythmicity,
 491                                                             &FGWinds::SetRhythmicity);
 492
 493   // Parameters for milspec turbulence
 494   PropertyManager->Tie("atmosphere/turbulence/milspec/windspeed_at_20ft_AGL-fps",
 495                        this, &FGWinds::GetWindspeed20ft,
 496                              &FGWinds::SetWindspeed20ft);
 497   PropertyManager->Tie("atmosphere/turbulence/milspec/severity",
 498                        this, &FGWinds::GetProbabilityOfExceedence,
 499                              &FGWinds::SetProbabilityOfExceedence);
 500
 501   // Total, calculated winds (local navigational/geographic frame: N-E-D). Read only.
 502   PropertyManager->Tie("atmosphere/total-wind-north-fps", this, eNorth, (PMF)&FGWinds::GetTotalWindNED);
 503   PropertyManager->Tie("atmosphere/total-wind-east-fps",  this, eEast,  (PMF)&FGWinds::GetTotalWindNED);
 504   PropertyManager->Tie("atmosphere/total-wind-down-fps",  this, eDown,  (PMF)&FGWinds::GetTotalWindNED);
 505
 506 }
 507
 508 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 509 //    The bitmasked value choices are as follows:
 510 //    unset: In this case (the default) JSBSim would only print
 511 //       out the normally expected messages, essentially echoing
 512 //       the config files as they are read. If the environment
 513 //       variable is not set, debug_lvl is set to 1 internally
 514 //    0: This requests JSBSim not to output any messages
 515 //       whatsoever.
 516 //    1: This value explicity requests the normal JSBSim
 517 //       startup messages
 518 //    2: This value asks for a message to be printed out when
 519 //       a class is instantiated
 520 //    4: When this value is set, a message is displayed when a
 521 //       FGModel object executes its Run() method
 522 //    8: When this value is set, various runtime state variables
 523 //       are printed out periodically
 524 //    16: When set various parameters are sanity checked and
 525 //       a message is printed out when they go out of bounds
 526
 527 void FGWinds::Debug(int from)
 528 {
 529   if (debug_lvl <= 0) return;
 530
 531   if (debug_lvl & 1) { // Standard console startup message output
 532     if (from == 0) { // Constructor
 533     }
 534   }
 535   if (debug_lvl & 2 ) { // Instantiation/Destruction notification
 536     if (from == 0) cout << "Instantiated: FGWinds" << endl;
 537     if (from == 1) cout << "Destroyed:    FGWinds" << endl;
 538   }
 539   if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
 540   }
 541   if (debug_lvl & 8 ) { // Runtime state variables
 542   }
 543   if (debug_lvl & 16) { // Sanity checking
 544   }
 545   if (debug_lvl & 128) { //
 546   }
 547   if (debug_lvl & 64) {
 548     if (from == 0) { // Constructor
 549       cout << IdSrc << endl;
 550       cout << IdHdr << endl;
 551     }
 552   }
 553 }
 554
 555 } // namespace JSBSim