Improvements to Tony's c172 model.

diff --git a/src/FDM/LaRCsim/c172_aero.c b/src/FDM/LaRCsim/c172_aero.c
index 019b3b789de2d9daf86d35c71b39e2ecedd5d597..d7b0164bdd8810261988c3b1e3a1975cd5413033 100644 (file)
--- a/src/FDM/LaRCsim/c172_aero.c
+++ b/src/FDM/LaRCsim/c172_aero.c
@@ -88,6 +88,8 @@
 #include "ls_cockpit.h"
 #include "ls_constants.h"
 #include "ls_types.h"
+#include "c172_aero.h"
+
 #include <math.h>
 #include <stdio.h>
 
@@ -144,84 +146,55 @@ void aero( SCALAR dt, int Initialize ) {
 
   
   static SCALAR trim_inc = 0.0002;
-  SCALAR long_trim;
 
-  
-  SCALAR elevator, aileron, rudder;
-  
-  
-  
   static SCALAR alpha_ind[NCL]={-0.087,0,0.175,0.209,0.24,0.262,0.278,0.303,0.314,0.332,0.367};        
   static SCALAR CLtable[NCL]={-0.14,0.31,1.21,1.376,1.51249,1.591,1.63,1.60878,1.53712,1.376,1.142};
-  
-  
-       
-  
-  /*Note that CLo,Cdo,Cmo will likely change with flap setting so 
-  they may not be declared static in the future */
-  
-  
-  static SCALAR CLadot=1.7;
-  static SCALAR CLq=3.9;
-  static SCALAR CLde=0.43;
-  static SCALAR CLo=0;
-  
-  
-  static SCALAR Cdo=0.031;
-  static SCALAR Cda=0.13;  /*Not used*/
-  static SCALAR Cdde=0.06;
-  
-  static SCALAR Cma=-0.89;
-  static SCALAR Cmadot=-5.2;
-  static SCALAR Cmq=-12.4;
-  static SCALAR Cmo=-0.062; 
-  static SCALAR Cmde=-1.28;
-  
-  static SCALAR Clbeta=-0.089;
-  static SCALAR Clp=-0.47;
-  static SCALAR Clr=0.096;
-  static SCALAR Clda=-0.178;
-  static SCALAR Cldr=0.0147;
-  
-  static SCALAR Cnbeta=0.065;
-  static SCALAR Cnp=-0.03;
-  static SCALAR Cnr=-0.099;
-  static SCALAR Cnda=-0.053;
-  static SCALAR Cndr=-0.0657;
-  
-  static SCALAR Cybeta=-0.31;
-  static SCALAR Cyp=-0.037;
-  static SCALAR Cyr=0.21;
-  static SCALAR Cyda=0.0;
-  static SCALAR Cydr=0.187;
-  
-  /*nondimensionalization quantities*/
-  /*units here are ft and lbs */
-  static SCALAR cbar=4.9; /*mean aero chord ft*/
-  static SCALAR b=35.8; /*wing span ft */
-  static SCALAR Sw=174; /*wing planform surface area ft^2*/
-  static SCALAR rPiARe=0.054; /*reciprocal of Pi*AR*e*/
-  
-  SCALAR W=Mass/INVG;
-  
-  SCALAR CLwbh,CL,cm,cd,cn,cy,croll,cbar_2V,b_2V,qS,qScbar,qSb,ps,rs;
-  
-  SCALAR F_X_wind,F_Y_wind,F_Z_wind,W_X,W_Y,W_Z;
-  
-  
-  
 
-  
-  if (Initialize != 0)
+ /*Note that CLo,Cdo,Cmo will likely change with flap setting so 
+  they may not be declared static in the future */
+   if (Initialize != 0)
     {
-      
-
-     
-
-      
+          CLadot=1.7;
+          CLq=3.9;
+          CLde=0.43;
+          CLo=0;
+
+
+          Cdo=0.031;
+          Cda=0.13;  /*Not used*/
+          Cdde=0.06;
+
+          Cma=-0.89;
+          Cmadot=-5.2;
+          Cmq=-12.4;
+          Cmo=-0.062; 
+          Cmde=-1.28;
+
+          Clbeta=-0.089;
+          Clp=-0.47;
+          Clr=0.096;
+          Clda=-0.178;
+          Cldr=0.0147;
+
+          Cnbeta=0.065;
+          Cnp=-0.03;
+          Cnr=-0.099;
+          Cnda=-0.053;
+          Cndr=-0.0657;
+
+          Cybeta=-0.31;
+          Cyp=-0.037;
+          Cyr=0.21;
+          Cyda=0.0;
+          Cydr=0.187;
+
+          /*nondimensionalization quantities*/
+          /*units here are ft and lbs */
+          cbar=4.9; /*mean aero chord ft*/
+          b=35.8; /*wing span ft */
+          Sw=174; /*wing planform surface area ft^2*/
+          rPiARe=0.054; /*reciprocal of Pi*AR*e*/
     }
-    
-  
   
   /*
   LaRCsim uses:
@@ -233,11 +206,12 @@ void aero( SCALAR dt, int Initialize ) {
        aileron > 0  => right wing up
        rudder > 0   => ANL
   */
-  
+  long_trim=0;
   if(Aft_trim) long_trim = long_trim - trim_inc;
   if(Fwd_trim) long_trim = long_trim + trim_inc;
   
-  /*scale pct control to degrees deflection*/
+/*   printf("Long_control: %7.4f, long_trim: %7.4f,DEG_TO_RAD: %7.4f, RAD_TO_DEG: %7.4f\n",Long_control,long_trim,DEG_TO_RAD,RAD_TO_DEG);
+ */  /*scale pct control to degrees deflection*/
   if ((Long_control+long_trim) <= 0)
        elevator=(Long_control+long_trim)*28*DEG_TO_RAD;
   else
@@ -274,11 +248,8 @@ void aero( SCALAR dt, int Initialize ) {
   qScbar=qS*cbar;
   qSb=qS*b;
   
-  /*transform the aircraft rotation rates*/
-  ps=-P_body*Cos_alpha + R_body*Sin_alpha;
-  rs=-P_body*Sin_alpha + R_body*Cos_alpha;
   
-/*   printf("Wb: %7.4f, Ub: %7.4f, Alpha: %7.4f, elev: %7.4f, ail: %7.4f, rud: %7.4f\n",W_body,U_body,Alpha*RAD_TO_DEG,elevator*RAD_TO_DEG,aileron*RAD_TO_DEG,rudder*RAD_TO_DEG);
+/*   printf("Wb: %7.4f, Ub: %7.4f, Alpha: %7.4f, elev: %7.4f, ail: %7.4f, rud: %7.4f, long_trim: %7.4f\n",W_body,U_body,Alpha*RAD_TO_DEG,elevator*RAD_TO_DEG,aileron*RAD_TO_DEG,rudder*RAD_TO_DEG,long_trim*RAD_TO_DEG);
   printf("Theta: %7.4f, Gamma: %7.4f, Beta: %7.4f, Phi: %7.4f, Psi: %7.4f\n",Theta*RAD_TO_DEG,Gamma_vert_rad*RAD_TO_DEG,Beta*RAD_TO_DEG,Phi*RAD_TO_DEG,Psi*RAD_TO_DEG);
  */
   
@@ -286,11 +257,11 @@ void aero( SCALAR dt, int Initialize ) {
   CLwbh = interp(CLtable,alpha_ind,NCL,Alpha);
   CL = CLo + CLwbh + (CLadot*Alpha_dot + CLq*Theta_dot)*cbar_2V + CLde*elevator;
   cd = Cdo + rPiARe*CL*CL + Cdde*elevator;
-  cy = Cybeta*Beta + (Cyp*ps + Cyr*rs)*b_2V + Cyda*aileron + Cydr*rudder;
+  cy = Cybeta*Beta + (Cyp*P_body + Cyr*R_body)*b_2V + Cyda*aileron + Cydr*rudder;
   
-  cm = Cmo + Cma*Alpha + (Cmq*Theta_dot + Cmadot*Alpha_dot)*cbar_2V + Cmde*(elevator+long_trim);
-  cn = Cnbeta*Beta + (Cnp*ps + Cnr*rs)*b_2V + Cnda*aileron + Cndr*rudder; 
-  croll=Clbeta*Beta + (Clp*ps + Clr*rs)*b_2V + Clda*aileron + Cldr*rudder;
+  cm = Cmo + Cma*Alpha + (Cmq*Q_body + Cmadot*Alpha_dot)*cbar_2V + Cmde*(elevator+long_trim);
+  cn = Cnbeta*Beta + (Cnp*P_body + Cnr*R_body)*b_2V + Cnda*aileron + Cndr*rudder; 
+  croll=Clbeta*Beta + (Clp*P_body + Clr*R_body)*b_2V + Clda*aileron + Cldr*rudder;
   
 /*   printf("CL: %7.4f, Cd: %7.4f, Cm: %7.4f, Cy: %7.4f, Cn: %7.4f, Cl: %7.4f\n",CL,cd,cm,cy,cn,croll);
  */  /*calculate wind axes forces*/
@@ -302,16 +273,12 @@ void aero( SCALAR dt, int Initialize ) {
  */  
   /*calculate moments and body axis forces */
   
-  /*find body-axis components of weight*/
-  /*with earth axis to body axis transform */
-  W_X=-1*W*Sin_theta;
-  W_Y=W*Sin_phi*Cos_theta;
-  W_Z=W*Cos_phi*Cos_theta;
+  
   
   /* requires ugly wind-axes to body-axes transform */
-  F_X_aero = W_X + F_X_wind*Cos_alpha*Cos_beta - F_Y_wind*Cos_alpha*Sin_beta - F_Z_wind*Sin_alpha;
-  F_Y_aero = W_Y + F_X_wind*Sin_beta + F_Y_wind*Cos_beta;
-  F_Z_aero = W_Z*NZ + F_X_wind*Sin_alpha*Cos_beta - F_Y_wind*Sin_alpha*Sin_beta + F_Z_wind*Cos_alpha;
+  F_X_aero = F_X_wind*Cos_alpha*Cos_beta - F_Y_wind*Cos_alpha*Sin_beta - F_Z_wind*Sin_alpha;
+  F_Y_aero = F_X_wind*Sin_beta + F_Y_wind*Cos_beta;
+  F_Z_aero = F_X_wind*Sin_alpha*Cos_beta - F_Y_wind*Sin_alpha*Sin_beta + F_Z_wind*Cos_alpha;
   
   /*no axes transform here */
   M_l_aero = croll*qSb;
@@ -319,10 +286,9 @@ void aero( SCALAR dt, int Initialize ) {
   M_n_aero = cn*qSb;
   
 /*   printf("I_yy: %7.4f, qScbar: %7.4f, qbar: %7.4f, Sw: %7.4f, cbar: %7.4f, 0.5*rho*V^2: %7.4f\n",I_yy,qScbar,Dynamic_pressure,Sw,cbar,0.5*0.0023081*V_rel_wind*V_rel_wind);
-  printf("Fxbody: %7.4f Fybody: %7.4f Fzbody: %7.4f Weight: %7.4f\n",F_X_wind,F_Y_wind,F_Z_wind,W);
-  printf("Maero: %7.4f Naero: %7.4f Raero: %7.4f\n",M_m_aero,M_n_aero,M_l_aero);
- */
-  
+ */  
+/*  printf("Fxaero: %7.4f Fyaero: %7.4f Fzaero: %7.4f Weight: %7.4f\n",F_X_aero,F_Y_aero,F_Z_aero,W);
+ *//*  printf("Maero: %7.4f Naero: %7.4f Raero: %7.4f\n",M_m_aero,M_n_aero,M_l_aero);
+ */  
 }
 
-

diff --git a/src/FDM/LaRCsim/c172_aero.h b/src/FDM/LaRCsim/c172_aero.h
new file mode 100644 (file)
index 0000000..fcbd85b
--- /dev/null
+++ b/src/FDM/LaRCsim/c172_aero.h
@@ -0,0 +1,55 @@
+/*c172_aero.h*/
+
+/*global declarations of aero model parameters*/
+
+  static SCALAR CLadot;
+  static SCALAR CLq;
+  static SCALAR CLde;
+  static SCALAR CLo;
+  
+  
+  static SCALAR Cdo;
+  static SCALAR Cda;  /*Not used*/
+  static SCALAR Cdde;
+  
+  static SCALAR Cma;
+  static SCALAR Cmadot;
+  static SCALAR Cmq;
+  static SCALAR Cmo; 
+  static SCALAR Cmde;
+  
+  static SCALAR Clbeta;
+  static SCALAR Clp;
+  static SCALAR Clr;
+  static SCALAR Clda;
+  static SCALAR Cldr;
+  
+  static SCALAR Cnbeta;
+  static SCALAR Cnp;
+  static SCALAR Cnr;
+  static SCALAR Cnda;
+  static SCALAR Cndr;
+  
+  static SCALAR Cybeta;
+  static SCALAR Cyp;
+  static SCALAR Cyr;
+  static SCALAR Cyda;
+  static SCALAR Cydr;
+  
+  /*nondimensionalization quantities*/
+  /*units here are ft and lbs */
+  static SCALAR cbar; /*mean aero chord ft*/
+  static SCALAR b; /*wing span ft */
+  static SCALAR Sw; /*wing planform surface area ft^2*/
+  static SCALAR rPiARe; /*reciprocal of Pi*AR*e*/
+  
+  
+  
+  SCALAR CLwbh,CL,cm,cd,cn,cy,croll,cbar_2V,b_2V,qS,qScbar,qSb,ps,rs;
+  
+  SCALAR F_X_wind,F_Y_wind,F_Z_wind;
+  
+  SCALAR long_trim;
+
+  
+  SCALAR elevator, aileron, rudder;

diff --git a/src/FDM/LaRCsim/c172_engine.c b/src/FDM/LaRCsim/c172_engine.c
index 14ff3054a4898078ce7b672db8ccdbd17d811954..c50604f3a8ebb081182a0376546c28d22102511c 100644 (file)
--- a/src/FDM/LaRCsim/c172_engine.c
+++ b/src/FDM/LaRCsim/c172_engine.c
@@ -80,5 +80,3 @@ void engine( SCALAR dt, int init ) {
 
     Throttle_pct = Throttle[3];
 }
-
-

diff --git a/src/FDM/LaRCsim/c172_gear.c b/src/FDM/LaRCsim/c172_gear.c
index c0c812f132ddd4eddb940d1f16f5cc852fdec9a3..8068815093285569baa76338d41d6f4642a2d73b 100644 (file)
--- a/src/FDM/LaRCsim/c172_gear.c
+++ b/src/FDM/LaRCsim/c172_gear.c
@@ -37,8 +37,8 @@
 
 $Header$
 $Log$
-Revision 1.2  1999/06/21 03:01:47  curt
-Updated for both JSBsim and Tony Peden's c172 flight model.
+Revision 1.3  1999/07/31 02:57:36  curt
+Improvements to Tony's c172 model.
 
 Revision 1.1.1.1  1999/04/05 21:32:45  curt
 Start of 0.6.x branch.
@@ -93,7 +93,6 @@ Initial Flight Gear revision.
 #include "ls_generic.h"
 #include "ls_cockpit.h"
 
-
 void sub3( DATA v1[],  DATA v2[], DATA result[] )
 {
     result[0] = v1[0] - v2[0];
@@ -137,6 +136,8 @@ void clear3( DATA v[] )
 void gear( SCALAR dt, int Initialize ) {
 char rcsid[] = "$Id$";
 
+  
+  
   /*
    * Aircraft specific initializations and data goes here
    */
@@ -181,7 +182,7 @@ char rcsid[] = "$Id$";
      *                V     V
      */
   
-  
+    
     static DATA sliding_mu   = 0.5;    
     static DATA rolling_mu   = 0.01;   
     static DATA max_brake_mu = 0.6;    
@@ -208,6 +209,8 @@ char rcsid[] = "$Id$";
 
     int i;                             /* per wheel loop counter */
   
+   Brake_pct=0; 
+  
   /*
    * Execution starts here
    */

diff --git a/src/FDM/LaRCsim/c172_init.c b/src/FDM/LaRCsim/c172_init.c
index d79eae47c02bb482b3ef8348714d32ccbc2c9374..a70299851cce8635b0bae4e6a7c665bf04b0e08d 100644 (file)
--- a/src/FDM/LaRCsim/c172_init.c
+++ b/src/FDM/LaRCsim/c172_init.c
@@ -74,3 +74,14 @@ void model_init( void ) {
   
   
 }
+/* a quick navion_init.h */
+
+
+#ifndef _NAVION_INIT_H
+#define _NAVION_INIT_H
+
+
+void model_init( void );
+
+
+#endif _NAVION_INIT_H