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Tweaked with drag and thrust.
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1 // LaRCsim.cxx -- interface to the LaRCsim flight model
2 //
3 // Written by Curtis Olson, started October 1998.
4 //
5 // Copyright (C) 1998  Curtis L. Olson  - curt@me.umn.edu
6 //
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
11 //
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 // General Public License for more details.
16 //
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 //
21 // $Id$
22
23
24
25
26
27 #include <FDM/LaRCsim/ls_cockpit.h>
28 #include <FDM/LaRCsim/ls_generic.h>
29 #include <FDM/LaRCsim/ls_interface.h>
30 #include <FDM/LaRCsim/ls_constants.h>
31 #include <FDM/LaRCsim/atmos_62.h>
32 /* #include <FDM/LaRCsim/ls_trim_fs.h> */
33 #include <FDM/LaRCsim/c172_aero.h>
34 #include <FDM/LaRCsim/ic.h>
35
36 #include <math.h>
37 #include <stdlib.h>
38 #include <stdio.h>
39 #include <string.h>
40
41
42
43
44 void do_trims(int kmax,FILE *out,InitialConditions IC)
45 {
46         int k=0,i,j;
47         double speed,elevator,cmcl,maxspeed;
48         out=fopen("trims.out","w");
49         speed=55;
50         
51         for(j=0;j<=30;j+=10)
52         {
53                 IC.flap_handle=j;
54                 for(i=1;i<=5;i++)
55                 {
56                         switch(i)
57                         {
58                                 case 1: IC.weight=1500;IC.cg=0.155;break;
59                                 case 2: IC.weight=1500;IC.cg=0.364;break;
60                                 case 3: IC.weight=1950;IC.cg=0.155;break;
61                                 case 4: IC.weight=2550;IC.cg=0.257;break;
62                                 case 5: IC.weight=2550;IC.cg=0.364;break;
63                         }
64
65                         speed=40;
66                         if(j > 0) { maxspeed = 90; }
67                         else { maxspeed = 170; }
68                         while(speed <= maxspeed)
69                         {
70                            IC.vc=speed;
71                            Long_control=0;Theta=0;Throttle_pct=0.0;
72
73                            k=trim_long(kmax,IC);
74                            if(Long_control <= 0)
75                                   elevator=Long_control*28;
76                            else
77                                  elevator=Long_control*23;      
78                            if(fabs(CL) > 1E-3)
79                            {
80                                         cmcl=cm / CL;
81                            }    
82                            if(k < kmax)
83                            {
84                                         fprintf(out,"%g,%g,%g,%g,%g,%d",V_calibrated_kts,Alpha*RAD_TO_DEG,Long_control,Throttle_pct,Flap_Position,k);
85                                         fprintf(out,",%g,%g,%g,%g,%g\n",CL,cm,cmcl,Weight,Cg);
86         /*                              printf("%g,%g,%g,%g,%g,%g,%g,%g,%g,%g\n",V_calibrated_kts,Alpha*RAD_TO_DEG,elevator,CL,cm,Cmo,Cma,Cmde,Mass*32.174,Dx_cg);
87          */                }    
88                    else
89                            {
90                                  printf("kmax exceeded at: %g knots, %g lbs, %g %%MAC, Flaps: %g\n",V_calibrated_kts,Weight,Cg,Flap_Position);
91                                  printf("wdot: %g, udot: %g, qdot: %g\n",W_dot_body,U_dot_body,Q_dot_body);
92                  printf("Alpha: %g, Throttle_pct: %g, Long_control: %g\n\n",Alpha*RAD_TO_DEG,Throttle_pct,Long_control);
93                            }
94                            speed+=10;     
95                         }
96         }
97         }       
98         fclose(out);
99 }       
100
101 void find_trim_stall(int kmax,FILE *out,InitialConditions IC)
102 {
103         int k=0,i,j;
104         int failf;
105         char axis[10];
106         double speed,elevator,cmcl,speed_inc,lastgood;
107         out=fopen("trim_stall.summary","w");
108         speed=90;
109         speed_inc=10;
110         //failf=malloc(sizeof(int));
111         
112         for(j=0;j<=30;j+=10)
113         {
114                 IC.flap_handle=j;
115                 for(i=1;i<=6;i++)
116                 {
117                         switch(i)
118                         {
119                                 case 1: IC.weight=1500;IC.cg=0.155;break;
120                                 case 2: IC.weight=1500;IC.cg=0.364;break;
121                                 case 3: IC.weight=2400;IC.cg=0.155;break;
122                                 case 4: IC.weight=2400;IC.cg=0.364;break;
123                                 case 5: IC.weight=2550;IC.cg=0.257;break;
124                                 case 6: IC.weight=2550;IC.cg=0.364;break;
125                         }
126
127                         speed=90;
128                         speed_inc=10;
129                         while(speed_inc >= 0.5)
130                         {
131                            IC.vc=speed;
132                            Long_control=0;Theta=0;Throttle_pct=0.0;
133                            failf=trim_longfr(kmax,IC);
134                            if(Long_control <= 0)
135                                   elevator=Long_control*28;
136                            else
137                                  elevator=Long_control*23;      
138                            if(fabs(CL) > 1E-3)
139                            {
140                                         cmcl=cm / CL;
141                            }    
142                            if(failf == 0)
143                            {
144                                         lastgood=speed;
145                                         axis[0]='\0';
146                                         //fprintf(out,"%g,%g,%g,%g,%g,%d",V_calibrated_kts,Alpha*RAD_TO_DEG,Long_control,Throttle_pct,Flap_Position,k);
147                                         //fprintf(out,",%g,%g,%g,%g,%g\n",CL,cm,cmcl,Weight,Cg);
148         /*                              printf("%g,%g,%g,%g,%g,%g,%g,%g,%g,%g\n",V_calibrated_kts,Alpha*RAD_TO_DEG,elevator,CL,cm,Cmo,Cma,Cmde,Mass*32.174,Dx_cg);
149          */                }    
150                    else
151                            {
152                                  printf("trim failed at: %g knots, %g lbs, %g %%MAC, Flaps: %g\n",V_calibrated_kts,Weight,Cg,Flap_Position);
153                                  printf("wdot: %g, udot: %g, qdot: %g\n",W_dot_body,U_dot_body,Q_dot_body);
154                  printf("Alpha: %g, Throttle_pct: %g, Long_control: %g\n\n",Alpha*RAD_TO_DEG,Throttle_pct,Long_control);
155                                  printf("Speed increment: %g\n",speed_inc);
156                                  speed+=speed_inc;
157                                  speed_inc/=2;
158                            }
159                            speed-=speed_inc;
160                            
161                                   
162                         }
163                         printf("failf %d\n",failf); 
164                         if(failf == 1)
165                            strcpy(axis,"lift");
166                         else if(failf == 2)
167                            strcpy(axis,"thrust");
168                         else if(failf == 3)
169                            strcpy(axis,"pitch");                  
170                         fprintf(out,"Last good speed: %g, Flaps: %g, Weight: %g, CG: %g, failed axis: %s\n",lastgood,Flap_handle,Weight,Cg,axis);
171
172                         
173         }
174         }
175         fclose(out);
176         //free(failf);
177 }       
178
179
180 // Initialize the LaRCsim flight model, dt is the time increment for
181 // each subsequent iteration through the EOM
182 int fgLaRCsimInit(double dt) {
183     ls_toplevel_init(dt);
184
185     return(1);
186 }
187
188
189
190 // Run an iteration of the EOM (equations of motion)
191 int main(int argc, char *argv[]) {
192     
193         
194         double save_alt = 0.0;
195     int multiloop=1,k=0,i,j;
196         double time=0,elev_trim,elev_trim_save,elevator,speed,cmcl;
197         FILE *out;
198         double hgain,hdiffgain,herr,herrprev,herr_diff,htarget;
199         double lastVt,vtdots,vtdott;
200         InitialConditions IC;
201     SCALAR *control[7];
202         SCALAR *state[7];
203         float old_state,effectiveness,tol,delta_state,lctrim;
204         float newcm,lastcm,cmalpha;
205         
206     if(argc < 6)
207         {
208             printf("Need args: $c172 speed alt alpha elev throttle\n");
209                 exit(1);
210         }       
211         initIC(&IC);
212         
213         IC.latitude=47.5299892; //BFI
214         IC.longitude=122.3019561;
215         Runway_altitude =   18.0;
216         IC.altitude=strtod(argv[2],NULL); 
217         IC.vc=strtod(argv[1],NULL);
218         IC.alpha=0;
219         IC.beta=0;
220         IC.gamma=strtod(argv[3],NULL);
221         IC.use_gamma_tmg=1;
222         IC.phi=0;
223         IC.psi=10;
224         IC.weight=2300;
225         IC.cg=0.25;
226         IC.flap_handle=0;
227         IC.long_control=strtod(argv[4],NULL);
228         IC.rudder_pedal=0;
229     
230         printf("IC.vc: %g\n",IC.vc);
231         ls_ForceAltitude(IC.altitude);  
232     fgLaRCsimInit(0.01);
233         printf("\nLong_control: %g\n\n",Long_control);
234         
235         
236         IC.cg=0.155;
237     IC.alpha=-5;
238         setIC(IC);ls_loop(0.0,-1);
239         newcm=CLwbh*(IC.cg - 0.557);
240         lastcm=newcm;
241         out=fopen("cmcl.out","w");
242         while(IC.alpha < 22)
243         {
244                 IC.alpha+=1;
245                 setIC(IC);ls_loop(0.0,-1);
246                 newcm=CLwbh*(IC.cg - 0.557);
247                 cmalpha=newcm-lastcm;
248                 printf("alpha: %4.0f, CL: %5.2f, Cm: %5.2f, Cma: %7.4f\n",Alpha*RAD_TO_DEG,CLwbh,newcm,cmalpha);
249                 fprintf(out,"%g %g\n",newcm,CLwbh);
250                 lastcm=newcm;
251         }       
252         fclose(out);
253         /* find_trim_stall(200,out,IC);
254         
255     IC.vc=120;
256         IC.altitude=8000;
257         IC.weight=2300;
258         IC.cg=0.25;
259         IC.flap_handle=0;
260
261         
262     setIC(IC);
263         printIC(IC);
264         k=trim_long(100,IC);
265
266         printf("Flap_handle: %g, Flap_Position: %g\n",Flap_handle,Flap_Position);
267         printf("k: %d, %g knots, %g lbs, %g %%MAC\n",k,V_calibrated_kts,Weight,Cg);
268         printf("wdot: %g, udot: %g, qdot: %g\n",W_dot_body,U_dot_body,Q_dot_body);
269     printf("Alpha: %g, Throttle_pct: %g, Long_control: %g\n\n",Alpha,Throttle_pct,Long_control);
270
271         printf("Cme: %g, elevator: %g, Cmde: %g\n",elevator*Cmde,elevator,Cmde);
272  
273     IC.cg=0.155;
274     setIC(IC);
275         k=trim_long(100,IC);
276
277         printf("Flap_handle: %g, Flap_Position: %g\n",Flap_handle,Flap_Position);
278         printf("k: %d, %g knots, %g lbs, %g %%MAC\n",k,V_calibrated_kts,Weight,Cg);
279         printf("wdot: %g, udot: %g, qdot: %g\n",W_dot_body,U_dot_body,Q_dot_body);
280     printf("Alpha: %g, Throttle_pct: %g, Long_control: %g\n\n",Alpha,Throttle_pct,Long_control);
281
282         printf("Cme: %g, elevator: %g, Cmde: %g\n",elevator*Cmde,elevator,Cmde);
283         
284         IC.cg=0.364;
285         setIC(IC);
286         k=trim_long(100,IC);
287
288         printf("Flap_handle: %g, Flap_Position: %g\n",Flap_handle,Flap_Position);
289         printf("k: %d, %g knots, %g lbs, %g %%MAC\n",k,V_calibrated_kts,Weight,Cg);
290         printf("wdot: %g, udot: %g, qdot: %g\n",W_dot_body,U_dot_body,Q_dot_body);
291     printf("Alpha: %g, Throttle_pct: %g, Long_control: %g\n\n",Alpha,Throttle_pct,Long_control);
292
293         printf("Cme: %g, elevator: %g, Cmde: %g\n",elevator*Cmde,elevator,Cmde);
294          */
295
296         
297         
298                                 
299         
300         /* do_trims(400,out,IC); */
301         
302         /* ls_loop(0.0,-1);
303         
304         control[1]=&IC.long_control;
305         control[2]=&IC.throttle;
306         control[3]=&IC.alpha;
307         control[4]=&IC.beta;
308         control[5]=&IC.phi;
309         control[6]=&IC.lat_control;
310         
311         state[1]=&Q_dot_body;state[2]=&U_dot_body;state[3]=&W_dot_body;
312         state[4]=&R_dot_body;state[5]=&V_dot_body;state[6]=&P_dot_body;
313         
314         
315         for(i=1;i<=6;i++)
316         {
317                 old_state=*state[i];
318             tol=1E-4;
319                 for(j=1;j<=6;j++)
320                 {
321                         *control[j]+=0.1;
322                         setIC(IC);
323                         ls_loop(0.0,-1);
324                         delta_state=*state[i]-old_state;
325                         effectiveness=(delta_state)/ 0.1;
326                         if(delta_state < tol)
327                                 effectiveness = 0;
328                         printf("%8.4f,",delta_state);
329                         *control[j]-=0.1;
330                         
331                 }
332                 printf("\n");
333                 setIC(IC);
334                 ls_loop(0.0,-1);
335         }                */
336         
337             return 1;
338 }
339
340 /*
341 void do_stick_pull(int kmax, SCALAR tmax,FILE *out,InitialConditions IC)
342 {
343         
344         SCALAR htarget,hgain,hdiffgain,herr,herr_diff,herrprev;
345         SCALAR theta_trim,elev_trim,time;
346         int k;
347         k=trim_long(kmax,IC);
348         printf("Trim:\n\tAlpha: %10.6f, elev: %10.6f, Throttle: %10.6f\n\twdot: %10.6f, qdot: %10.6f, udot: %10.6f\n",Alpha*RAD_TO_DEG,Long_control,Throttle_pct,W_dot_body,U_dot_body,Q_dot_body);
349
350         
351         htarget=0;
352         
353         hgain=1;
354         hdiffgain=1;
355         elev_trim=Long_control;
356         out=fopen("stick_pull.out","w");
357         herr=Q_body-htarget;
358                 
359         //fly steady-level for 2 seconds, well, zero pitch rate anyway
360         while(time < 2.0)
361         {
362                  herrprev=herr;
363                  ls_update(1);
364                  herr=Q_body-htarget;
365                  herr_diff=herr-herrprev;
366                  Long_control=elev_trim+(hgain*herr + hdiffgain*herr_diff);
367                  time+=0.01;  
368                  //printf("Time: %7.4f, Alt: %7.4f, Alpha: %7.4f, pelev: %7.4f, qdot: %7.4f, udot: %7.4f, Phi: %7.4f, Psi: %7.4f\n",time,Altitude,Alpha*RAD_TO_DEG,Long_control*100,Q_body*RAD_TO_DEG,U_dot_body,Phi,Psi);
369          //printf("Mcg: %7.4f, Mrp: %7.4f, Maero: %7.4f, Meng: %7.4f, Mgear: %7.4f, Dx_cg: %7.4f, Dz_cg: %7.4f\n\n",M_m_cg,M_m_rp,M_m_aero,M_m_engine,M_m_gear,Dx_cg,Dz_cg);
370                  fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,",time,V_true_kts,Theta*RAD_TO_DEG,Alpha*RAD_TO_DEG,Q_body*RAD_TO_DEG,Alpha_dot*RAD_TO_DEG,Q_dot_body*RAD_TO_DEG,Throttle_pct,elevator*RAD_TO_DEG);
371                  fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f\n",CL,CLwbh,cm,cd,Altitude);
372         }
373
374         //begin untrimmed climb at theta_trim + 2 degrees
375         hgain=4;
376         hdiffgain=2;
377         theta_trim=Theta;
378         htarget=theta_trim;
379         herr=Theta-htarget;
380         while(time < tmax)
381         {
382                 //ramp in the target theta
383                 if(htarget < (theta_trim + 2*DEG_TO_RAD))
384                 {
385                         htarget+= 0.01*DEG_TO_RAD;
386                 }       
387                 herrprev=herr;
388                  ls_update(1);
389                  herr=Theta-htarget;
390                  herr_diff=herr-herrprev;
391                  Long_control=elev_trim+(hgain*herr + hdiffgain*herr_diff);
392                  time+=0.01;  
393                  //printf("Time: %7.4f, Alt: %7.4f, Alpha: %7.4f, pelev: %7.4f, qdot: %7.4f, udot: %7.4f, Phi: %7.4f, Psi: %7.4f\n",time,Altitude,Alpha*RAD_TO_DEG,Long_control*100,Q_body*RAD_TO_DEG,U_dot_body,Phi,Psi);
394          //printf("Mcg: %7.4f, Mrp: %7.4f, Maero: %7.4f, Meng: %7.4f, Mgear: %7.4f, Dx_cg: %7.4f, Dz_cg: %7.4f\n\n",M_m_cg,M_m_rp,M_m_aero,M_m_engine,M_m_gear,Dx_cg,Dz_cg);
395                  fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,",time,V_true_kts,Theta*RAD_TO_DEG,Alpha*RAD_TO_DEG,Q_body*RAD_TO_DEG,Alpha_dot*RAD_TO_DEG,Q_dot_body*RAD_TO_DEG,Throttle_pct,elevator*RAD_TO_DEG);
396                  fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f\n",CL,CLwbh,cm,cd,Altitude);
397         }
398         printf("%g,%g\n",theta_trim*RAD_TO_DEG,htarget*RAD_TO_DEG);      
399         fclose(out);
400 }       
401
402 void do_takeoff(FILE *out)
403 {
404         SCALAR htarget,hgain,hdiffgain,elev_trim,elev_trim_save,herr;
405         SCALAR time,herrprev,herr_diff;
406         
407         htarget=0;
408         
409         hgain=1;
410         hdiffgain=1;
411         elev_trim=Long_control;
412         elev_trim_save=elev_trim;
413         
414         
415         out=fopen("takeoff.out","w");
416         herr=Q_body-htarget;
417                  
418                 // attempt to maintain zero pitch rate during the roll
419                 while((V_calibrated_kts < 61) && (time < 30.0))
420                 {
421                         // herrprev=herr
422                         ls_update(1);
423                         // herr=Q_body-htarget;
424                         // herr_diff=herr-herrprev;
425                         // Long_control=elev_trim+(hgain*herr + hdiffgain*herr_diff); 
426                         time+=0.01;  
427                         printf("Time: %7.4f, Vc: %7.4f, Alpha: %7.4f, pelev: %7.4f, qdot: %7.4f, udot: %7.4f, U: %7.4f, W: %7.4f\n",time,V_calibrated_kts,Alpha*RAD_TO_DEG,Long_control*100,Q_body*RAD_TO_DEG,U_dot_body,U_body,W_body);
428 //              printf("Mcg: %7.4f, Mrp: %7.4f, Maero: %7.4f, Meng: %7.4f, Mgear: %7.4f, Dx_cg: %7.4f, Dz_cg: %7.4f\n\n",M_m_cg,M_m_rp,M_m_aero,M_m_engine,M_m_gear,Dx_cg,Dz_cg);
429 //                      fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,",time,V_calibrated_kts,Theta*RAD_TO_DEG,Alpha*RAD_TO_DEG,Q_body*RAD_TO_DEG,Alpha_dot*RAD_TO_DEG,Q_dot_body*RAD_TO_DEG,Throttle_pct,elevator*RAD_TO_DEG);
430                         fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f\n",CL,CLwbh,cm,cd,Altitude);
431                         
432                 }
433                 //At Vr, ramp in 10% nose up elevator in 0.5 seconds
434                 elev_trim_save=0;
435                 printf("At Vr, rotate...\n");
436                 while((Q_body < 3.0*RAD_TO_DEG) && (time < 30.0))
437                 {
438                         Long_control-=0.01;
439                         ls_update(1);
440                         printf("Time: %7.4f, Vc: %7.4f, Alpha: %7.4f, pelev: %7.4f, q: %7.4f, cm: %7.4f, U: %7.4f, W: %7.4f\n",time,V_calibrated_kts,Alpha*RAD_TO_DEG,Long_control*100,Q_body*RAD_TO_DEG,cm,U_body,W_body);
441
442                         fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,",time,V_calibrated_kts,Theta*RAD_TO_DEG,Alpha*RAD_TO_DEG,Q_body*RAD_TO_DEG,Alpha_dot*RAD_TO_DEG,Q_dot_body*RAD_TO_DEG,Throttle_pct,elevator*RAD_TO_DEG);
443                         fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f\n",CL,CLwbh,cm,cd,Altitude);
444                         time +=0.01;
445
446                 }
447                 //Maintain 15 degrees theta for the climbout
448                 htarget=15*DEG_TO_RAD;
449                 herr=Theta-htarget;
450                 hgain=10;
451                 hdiffgain=1;
452                 elev_trim=Long_control;
453                 while(time < 30.0)
454                 {
455                         herrprev=herr;
456                         ls_update(1);
457                         herr=Theta-htarget;
458                         herr_diff=herr-herrprev;
459                         Long_control=elev_trim+(hgain*herr + hdiffgain*herr_diff);
460                         time+=0.01;  
461                         printf("Time: %7.4f, Alt: %7.4f, Speed: %7.4f, Theta: %7.4f\n",time,Altitude,V_calibrated_kts,Theta*RAD_TO_DEG);
462                         fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,%20.8f,",time,V_calibrated_kts,Theta*RAD_TO_DEG,Alpha*RAD_TO_DEG,Q_body*RAD_TO_DEG,Alpha_dot*RAD_TO_DEG,Q_dot_body*RAD_TO_DEG,Throttle_pct,elevator*RAD_TO_DEG);
463                         fprintf(out,"%20.8f,%20.8f,%20.8f,%20.8f,%20.8f\n",CL,CLwbh,cm,cd,Altitude);
464                 }       
465                 fclose(out);    
466                 printf("Speed: %7.4f, Alt: %7.4f, Alpha: %7.4f, pelev: %7.4f, q: %7.4f, udot: %7.4f\n",V_true_kts,Altitude,Alpha*RAD_TO_DEG,Long_control,Q_body*RAD_TO_DEG,U_dot_body);
467                 printf("F_down_total: %7.4f, F_Z_aero: %7.4f, F_X: %7.4f, M_m_cg: %7.4f\n\n",F_down+Mass*Gravity,F_Z_aero,F_X,M_m_cg);
468
469    
470     
471     
472 }
473 */
474
475
476