src/robofsm/motion-control.cc

   1 /**
   2  * @file   motion-control.cc
   3  * @author Michal Sojka <sojkam1@fel.cvut.cz>, Petr Beneš
   4  * @date   Fri Mar 20 10:36:59 2009
   5  *
   6  * @brief
   7  *
   8  *
   9  */
  10
  11 //#define MOTION_DEBUG
  12
  13 #ifdef MOTION_DEBUG
  14     #define DBG(format, ...) printf(format, ##__VA_ARGS__)
  15     #define DBGflush() fflush(stdout)
  16 #else
  17     #define DBG(format, ...)
  18     #define DBGflush()
  19 #endif
  20
  21 #include <sys/time.h>
  22 #include <time.h>
  23 #include "trgen.h"
  24 #include "balet.h"
  25 #include <robodata.h>
  26 #include <robot.h>
  27 #include <pthread.h>
  28 #include <path_planner.h>
  29 #include <signal.h>
  30 #include <movehelper.h>
  31 #include <sharp.h>
  32 #include <unistd.h>
  33 #include <map.h>
  34 #include "robot_config.h"
  35 #include <robomath.h>
  36
  37 #define MOTION_CONTROL
  38 #include "motion-control.h"
  39
  40 /* ULoPoS EKF */
  41 #include <ekf.h>
  42 #include <geom.h>
  43
  44 /* ULoPoS constants (-%-TEMPERATURE-%- dependent!) */
  45 #define SOUND_VELOCITY   (331.3+0.606*20)
  46 #define XCORR2METER      (SOUND_VELOCITY*(127.0/508.0)/3000.0)
  47 #define D_MAX            (XCORR2METER*508.0)
  48
  49 /*******************************************************************************
  50  * Controller thread and helper functions for that thread
  51  *******************************************************************************/
  52
  53 /**
  54  * If the distance of robot's estimated position from robot's
  55  * requested position if above this value, the robot lost and we try
  56  * to reset localization.
  57  */
  58 #define MAX_POS_ERROR_M 0.5
  59
  60 /**
  61  * If trajectory end is reached and robot's estimated position is
  62  * closer than this distance, the movement is considered as "done".
  63  */
  64 #define CLOSE_TO_TARGET_M 0.1
  65
  66 //Controller gains
  67 const struct balet_params k = {
  68   p_tangent:  3,                // dx gain
  69   p_angle: 2,                   // dphi gain
  70   p_perpen: 5                   // dy gain
  71 //   p_tangent:  0.2,           // dx gain
  72 //   p_angle: 0.15,                     // dphi gain
  73 //   p_perpen: 1                        // dy gain
  74 };
  75
  76 #define MOTION_PERIOD_NS (50/*ms*/*1000*1000)
  77 #define MEASURE_TIMEOUT_NS (100/*ms*/*1000*1000)
  78
  79 #define SIG_DO_CONTROL_NOW (SIGRTMIN+1)
  80
  81 // Global varibles
  82 static pthread_t thr_trajectory_follower;
  83 static struct timeval tv_start; /**< Absolute time, when trajectory started. */
  84
  85 /** Stores the actually followed trajectory object */
  86 static Trajectory *actual_trajectory;
  87 static pthread_mutex_t actual_trajectory_lock;
  88
  89 // Trajectory recalculation
  90 sem_t recalculation_not_running;
  91 sem_t measurement_received;
  92
  93 /**
  94  * Determines way of thread_trajectory_follower() operation:
  95  * - 0 measurement doesn't work, controller invocation based on time (formerly CONFIG_OPEN_LOOP)
  96  * - 2 measurement works, controller invocation based on sem_post
  97  * - 1 measurement doesn't work and stop() was called
  98  */
  99 int measurement_ok = 0;
 100
 101
 102
 103 static void delete_actual_trajectory()
 104 {
 105         Trajectory *old;
 106         pthread_mutex_lock(&actual_trajectory_lock);
 107         old = actual_trajectory;
 108         actual_trajectory = NULL;
 109         pthread_mutex_unlock(&actual_trajectory_lock);
 110         robot_send_speed(0,0);
 111         if (old) delete(actual_trajectory);
 112 }
 113
 114 /** Sends events from follower thread to FSM. */
 115 static void notify_fsm(bool done, double error)
 116 {
 117         static bool done_sent;
 118         static bool lost_sent = false;
 119
 120         if (error > MAX_POS_ERROR_M) {
 121                 if (!lost_sent) {
 122                         lost_sent = true;
 123                         FSM_SIGNAL(MOTION, EV_TRAJECTORY_LOST, NULL);
 124                 }
 125         } else {
 126                 lost_sent = false;
 127                 if (done) {
 128                         if (error < CLOSE_TO_TARGET_M) {
 129                                 FSM_SIGNAL(MOTION, EV_TRAJECTORY_DONE_AND_CLOSE, NULL);
 130                         } else if (!done_sent) {
 131                                 done_sent = true;
 132                                 FSM_SIGNAL(MOTION, EV_TRAJECTORY_DONE, NULL);
 133                         }
 134                 } else {
 135                         done_sent = false;
 136                 }
 137         }
 138 }
 139
 140 static void check_for_collision_in_future(Trajectory *traj, double current_time)
 141 {
 142         Pos future_pos;
 143         struct map *map = robot.map;
 144         int xcell, ycell;
 145         double x, y;
 146         bool valid;
 147         unsigned i;
 148 //      const double times[] = { 0.5, 0.3, 0.1 }; // seconds
 149         const double times[] = { 0.3, 0.4, 0.5, 0.7, 0.9, 1.1 }; // seconds
 150
 151
 152         for (i=0; i < sizeof(times)/sizeof(times[0]); i++) {
 153                 traj->getRefPos(current_time+times[i], future_pos);
 154
 155                 /* Ignore obstacles when turning */
 156                 if (fabs(future_pos.v) < 0.01)
 157                         continue;
 158
 159                 x = future_pos.x + cos(future_pos.phi)*ROBOT_AXIS_TO_BRUSH_M;
 160                 y = future_pos.y + sin(future_pos.phi)*ROBOT_AXIS_TO_BRUSH_M;
 161
 162                 ShmapPoint2Cell(x, y, &xcell, &ycell, &valid);
 163                 if (!valid)
 164                         continue;
 165                 if (map->cells[ycell][xcell].detected_obstacle > 0) {
 166                         if (sem_trywait(&recalculation_not_running) == 0) {
 167                                 FSM_SIGNAL(MOTION, EV_OBSTACLE, NULL);
 168                                 break;
 169                         }
 170                 }
 171         }
 172 }
 173
 174 static void do_estimation()
 175 {
 176         static real_t beacon_xy[3][2] = {
 177                 { 3.062, -0.05},
 178                 {-0.062,  1.05},
 179                 { 3.062,  2.162},
 180         };
 181         static ekf8_t ekf8;
 182         static uint32_t odo0[2];
 183         static real_t y[5] = {0.0, 0.0, 0.0, 0.0, 0.0};
 184         static int missing_odo_count = 0;
 185         uint32_t t[3], odo[2];
 186         real_t x[8], P[8*8];
 187         int i, odo_received, err[5];
 188
 189         /* locks should not be necessary, however... */
 190         ROBOT_LOCK(corr_distances);
 191         t[0] = robot.corr_distances.t1;
 192         t[1] = robot.corr_distances.t2;
 193         t[2] = robot.corr_distances.t3;
 194         ROBOT_UNLOCK(corr_distances);
 195         ROBOT_LOCK(motion_irc);
 196         odo[0] = robot.motion_irc.left;
 197         odo[1] = robot.motion_irc.right;
 198         odo_received = robot.motion_irc_received;
 199         robot.motion_irc_received = 0;
 200         ROBOT_UNLOCK(motion_irc);
 201
 202         for (i = 0; i < 3; i++)
 203                 y[i] = (XCORR2METER/32.0)*t[i];
 204
 205         /* missing odometry workaround :-( */
 206         if (odo_received) {
 207                 real_t c = 1.0/(real_t)(1 + missing_odo_count);
 208                 y[3] = c*ODO_C*(real_t)((int32_t)(odo0[0] - odo[0]));
 209                 y[4] = c*ODO_C*(real_t)((int32_t)(odo[1] - odo0[1]));
 210                 missing_odo_count = 0;
 211         }
 212         else
 213                 ++missing_odo_count;
 214
 215         odo0[0] = odo[0];  odo0[1] = odo[1];
 216         DBG("UZV+ODO:  %f  %f  %f  %f  %f\n", y[0], y[1], y[2], y[3], y[4]);
 217         //DBG("ODO:  %f  %f    %u  %u\n", y[3], y[4], odo[0], odo[1]);
 218
 219         if (init_ekf_flag) {
 220                 /*FIXME:reflect init pos & beacon coords accord.to our color */
 221                 ROBOT_LOCK(est_pos);
 222                 real_t xy0[] = {robot.est_pos.x, robot.est_pos.y};
 223                 y[3] = y[4] = 0.0;
 224                 ekf8_init(&ekf8, (real_t*)beacon_xy, D_MAX, 30.0, xy0, y);
 225                 ekf8.ekf.x[6] = robot.est_pos.phi;
 226                 init_ekf_flag = false;
 227                 ROBOT_UNLOCK(est_pos);
 228         }
 229
 230         ekf8_step(&ekf8, x, P, err, y);
 231
 232         DBG("EKF: x=%f   y=%f   phi=%8.4f\n", x[0], x[1], x[6]*(180.0/M_PI));
 233
 234         ROBOT_LOCK(est_pos);
 235         robot.est_pos.x = x[0] - ODO_D*cos(x[6]);
 236         robot.est_pos.y = x[1] - ODO_D*sin(x[6]);
 237         robot.est_pos.phi = x[6];
 238         ROBOT_UNLOCK(est_pos);
 239 }
 240
 241 static void do_control()
 242 {
 243         double speedl, speedr;
 244
 245         double t;
 246         struct timeval tv;
 247
 248         // Calculate reference position
 249         /***FIXME:should not rely on system clock, the period is fixed***/
 250         gettimeofday(&tv, NULL);
 251         t = (double)(tv.tv_usec - tv_start.tv_usec) / 1000000.0;
 252         t += (tv.tv_sec - tv_start.tv_sec);
 253 /*
 254         // check for new trajectory to switch
 255         // only if the trajectory is already prepared
 256         if (switch_to_trajectory != NULL && t >= switch_time) {
 257                 pthread_mutex_lock(&switch_to_trajectory_lock);
 258
 259                 DBG("SWITCHING to new trajectory\n");
 260
 261                 go(switch_to_trajectory);
 262                 // nothing prepared now
 263                 switch_to_trajectory = NULL;
 264                 pthread_mutex_unlock(&switch_to_trajectory_lock);
 265         }
 266 */
 267         pthread_mutex_lock(&actual_trajectory_lock);
 268         Trajectory *w = actual_trajectory;
 269         if (w) {
 270                 Pos ref_pos, est_pos, balet_out;
 271                 bool done;
 272
 273                 // Calculate reference position
 274                 gettimeofday(&tv, NULL);
 275                 t = (double)(tv.tv_usec - tv_start.tv_usec) / 1000000.0;
 276                 t += (tv.tv_sec - tv_start.tv_sec);
 277
 278                 // if switch_to_trajectory is being prepared, it can not stop calculation
 279                 // and start to count again, it could evoke overloading
 280                 if (robot.obstacle_avoidance_enabled)
 281                         check_for_collision_in_future(w, t);
 282
 283
 284                 done = w->getRefPos(t, ref_pos);
 285
 286                 if (ref_pos.omega > actual_trajectory->constr.maxomega)
 287                         DBG("Omega constraint problem %lf, max %lf -------------------- \n", ref_pos.omega, actual_trajectory->constr.maxomega);
 288
 289                 ROBOT_LOCK(ref_pos);
 290                 robot.ref_pos.x = ref_pos.x;
 291                 robot.ref_pos.y = ref_pos.y;
 292                 robot.ref_pos.phi = ref_pos.phi;
 293                 ROBOT_UNLOCK(ref_pos);
 294
 295                 ROBOT_LOCK(est_pos);
 296                 est_pos.x = robot.est_pos.x;
 297                 est_pos.y = robot.est_pos.y;
 298                 est_pos.phi = robot.est_pos.phi;
 299                 ROBOT_UNLOCK(est_pos);
 300
 301                 if (measurement_ok < 2) {
 302                         // We don't have any feedback now. It is
 303                         // supposed that the estimated position is
 304                         // equal to the reference position.
 305                         robot_set_est_pos_notrans(ref_pos.x, ref_pos.y, ref_pos.phi);
 306                         est_pos.x = ref_pos.x;
 307                         est_pos.y = ref_pos.y;
 308                         est_pos.phi = ref_pos.phi;
 309                 }
 310
 311 #ifdef MOTION_PRINT_REF
 312                 static double last_t;
 313                 if (t < last_t) last_t = t; // Switched to a new trajectory
 314                 printf("rx=%5.02f ry=%5.02f, rphi=%4.0f v=%-4.02f  omega=%-4.02f, time=%lf dt=%lf \n", ref_pos.x, ref_pos.y, ref_pos.phi/M_PI*180, ref_pos.v, ref_pos.omega, t, t-last_t);
 315                 fflush(stdout);
 316                 last_t = t;
 317 #endif
 318
 319                 // Call the controller
 320                 double error;
 321                 error = balet(ref_pos, est_pos, k, balet_out);
 322                 speedl = balet_out.v - ROBOT_ROTATION_RADIUS_M*balet_out.omega;
 323                 speedr = balet_out.v + ROBOT_ROTATION_RADIUS_M*balet_out.omega;
 324                 notify_fsm(done, error);
 325         } else {
 326                 speedl = 0;
 327                 speedr = 0;
 328         }
 329
 330
 331         // Apply controller output
 332         robot_send_speed(speedl, speedr);
 333         pthread_mutex_unlock(&actual_trajectory_lock);
 334 }
 335
 336 void dummy_handler(int)
 337 {
 338 }
 339
 340 static inline void next_period(struct timespec *next, long long interval_ns)
 341 {
 342         next->tv_nsec += interval_ns;
 343         if (next->tv_nsec >= 1000000000) {
 344                 next->tv_sec++;
 345                 next->tv_nsec -= 1000000000;
 346         }
 347 }
 348
 349 /**
 350  * A thread running the controller.
 351  *
 352  * This (high priority) thread executes the motion control
 353  * algorithm. It calculates repference position based on actual
 354  * trajectory and current time. Then it calls "balet" controller to
 355  * close feedback.
 356  *
 357  * @param arg
 358  *
 359  * @return
 360  */
 361 void *thread_trajectory_follower(void *arg)
 362 {
 363         struct timespec next;
 364         int ret;
 365
 366         clock_gettime(CLOCK_REALTIME, &next);
 367
 368         while (1) {
 369                 ret = sem_timedwait(&measurement_received, &next);
 370
 371                 if (ret == -1 && errno == ETIMEDOUT) {
 372                         next_period(&next, MOTION_PERIOD_NS);
 373                         if (measurement_ok) {
 374                                 if (measurement_ok == 2) {
 375                                         fprintf(stderr, "problem: measurement timeout!!!!!!!!!!!");
 376                                 }
 377                                 measurement_ok--;
 378                         }
 379
 380
 381                 } else {
 382                         next_period(&next, MEASURE_TIMEOUT_NS);
 383                         if (measurement_ok < 2) {
 384                                 measurement_ok++;
 385                         }
 386                 }
 387
 388                 robot.localization_works = (measurement_ok == 2);
 389                 if (measurement_ok == 2) {
 390                         do_estimation();
 391                 }
 392                 do_control();
 393
 394         }
 395 }
 396
 397 /**
 398  * Tells trajctory_follower to start moving along trajectory @c t.
 399  *
 400  * @param t Trajectory to follow.
 401  * @param append_time Relative time from the beginning of the @c actual_trajectory
 402  * when to append the new one
 403  */
 404 void go(Trajectory *t, double append_time)
 405 {
 406         pthread_mutex_lock(&actual_trajectory_lock);
 407         Trajectory *old;
 408         if (actual_trajectory && append_time != 0) {
 409                 // trajectory only connects a new one in some specific time
 410                 if(!actual_trajectory->appendTrajectory(*t, append_time))
 411                         DBG("Can not append trajectory\n");
 412         } else {
 413                 // trajectory starts from zero time
 414                 old = actual_trajectory;
 415                 gettimeofday(&tv_start, NULL);
 416                 actual_trajectory = t;
 417 #ifdef MOTION_LOG
 418                 t->logTraj(tv_start.tv_sec + 1e-6*tv_start.tv_usec);
 419 #endif
 420                 if (old)
 421                         delete(old);
 422         }
 423         pthread_mutex_unlock(&actual_trajectory_lock);
 424 }
 425
 426 /**
 427  * switches to newly calculated trajectory to go on it at specific time
 428  */
 429 /*void switch_trajectory_at(Trajectory *t, double time)
 430 {
 431         pthread_mutex_lock(&switch_to_trajectory_lock);
 432         switch_to_trajectory = t;
 433         switch_time = time;
 434         pthread_mutex_unlock(&switch_to_trajectory_lock);
 435
 436         struct timeval tv;
 437         gettimeofday(&tv, NULL);
 438         double tm = (double)(tv.tv_usec - tv_start.tv_usec) / 1000000.0;
 439         tm += (tv.tv_sec - tv_start.tv_sec);
 440         if (switch_time <= tm)
 441                 DBG("//// BAD SWITCH ////");
 442 }
 443 */
 444 void stop()
 445 {
 446         delete_actual_trajectory();
 447
 448         // Interrupt sem_timedwait() in thread_trajectory_follower(),
 449         // so we stop immediately.
 450         sem_post(&measurement_received);
 451 }
 452
 453 /**
 454  * Initializes motion controller.
 455  *
 456  *
 457  * @return Zero on success, non-zero otherwise.
 458  */
 459 int motion_control_init()
 460 {
 461         pthread_attr_t tattr;
 462         sched_param param;
 463         pthread_mutexattr_t mattr;
 464         int ret;
 465
 466         actual_trajectory = NULL;
 467         //switch_to_trajectory = NULL;
 468
 469
 470         ret = pthread_mutexattr_init(&mattr);
 471 #ifdef HAVE_PRIO_INHERIT
 472         ret = pthread_mutexattr_setprotocol(&mattr, PTHREAD_PRIO_INHERIT);
 473 #endif
 474         pthread_mutex_init(&actual_trajectory_lock, &mattr);
 475
 476         sem_init(&recalculation_not_running, 0, 1);
 477
 478         // Trajectory follower thread
 479         sem_init(&measurement_received, 0, 0);
 480         pthread_attr_init (&tattr);
 481         pthread_attr_getschedparam (&tattr, &param);
 482         pthread_attr_setschedpolicy(&tattr, SCHED_FIFO);
 483         param.sched_priority = THREAD_PRIO_TRAJ_FOLLOWER;
 484         ret = pthread_attr_setschedparam (&tattr, &param);
 485         if(ret) {
 486                 perror("move_init: pthread_attr_setschedparam(follower)");
 487                 goto err;
 488         }
 489         ret = pthread_create(&thr_trajectory_follower, &tattr, thread_trajectory_follower, NULL);
 490         if(ret) {
 491                 perror("move_init: pthread_create");
 492                 goto err;
 493         }
 494
 495         return 0;
 496   err:
 497         return ret;
 498 }
 499
 500 void motion_control_done()
 501 {
 502         pthread_cancel(thr_trajectory_follower);
 503         pthread_join(thr_trajectory_follower, NULL);
 504
 505         robot.orte.motion_speed.right = 0;
 506         robot.orte.motion_speed.left = 0;
 507         ORTEPublicationSend(robot.orte.publication_motion_speed);
 508 }
 509
 510
 511 void get_future_pos(double rel_time_sec, Pos &pos, double &switch_time)
 512 {
 513         struct timeval tv;
 514
 515         gettimeofday(&tv, NULL);
 516         switch_time = (double)(tv.tv_usec - tv_start.tv_usec) / 1000000.0;
 517         switch_time += (tv.tv_sec - tv_start.tv_sec);
 518         switch_time += rel_time_sec;
 519
 520         pthread_mutex_lock(&actual_trajectory_lock);
 521         if (actual_trajectory) {
 522                 actual_trajectory->getRefPos(switch_time, pos);
 523                 pthread_mutex_unlock(&actual_trajectory_lock);
 524         } else {
 525                 // Robot doesn't move, so return current position
 526                 pthread_mutex_unlock(&actual_trajectory_lock);
 527
 528                 ROBOT_LOCK(est_pos);
 529                 pos.x = robot.est_pos.x;
 530                 pos.y = robot.est_pos.y;
 531                 pos.phi = robot.est_pos.phi;
 532                 pos.v = 0;
 533                 pos.omega = 0;
 534                 ROBOT_UNLOCK(est_pos);
 535         }
 536 }