src/rrts.cc

   1 #include <algorithm>
   2 #include "rrts.h"
   3
   4 #include "reeds_shepp.h"
   5
   6 template <typename T> int sgn(T val) {
   7         return (T(0) < val) - (val < T(0));
   8 }
   9
  10 RRTNode::RRTNode()
  11 {
  12 }
  13
  14 RRTNode::RRTNode(const BicycleCar &bc)
  15 {
  16     this->x(bc.x());
  17     this->y(bc.y());
  18     this->h(bc.h());
  19     this->sp(bc.sp());
  20     this->st(bc.st());
  21 }
  22
  23 bool RRTNode::operator==(const RRTNode& n)
  24 {
  25         if (this == &n)
  26                 return true;
  27         return false;
  28 }
  29
  30 Obstacle::Obstacle()
  31 {
  32 }
  33
  34 double RRTS::elapsed()
  35 {
  36         std::chrono::duration<double> dt;
  37         dt = std::chrono::duration_cast<std::chrono::duration<double>>(
  38                 std::chrono::high_resolution_clock::now()
  39                 - this->tstart_
  40         );
  41         this->scnt_ = dt.count();
  42         return this->scnt_;
  43 }
  44
  45 void RRTS::log_path_cost()
  46 {
  47         this->log_path_cost_.push_back(cc(this->goals().front()));
  48         this->log_path_time_ += 0.1;
  49 }
  50
  51 bool RRTS::should_stop()
  52 {
  53         // the following counters must be updated, do not comment
  54         this->icnt_++;
  55         this->elapsed();
  56         // current iteration stop conditions
  57         if (this->should_finish()) return true;
  58         if (this->should_break()) return true;
  59         // but continue by default
  60         return false;
  61 }
  62
  63 bool RRTS::should_finish()
  64 {
  65         // decide finish conditions (maybe comment some lines)
  66         //if (this->icnt_ > 999) return true;
  67         if (this->scnt_ > 2) return true;
  68         //if (this->gf()) return true;
  69         // but continue by default
  70         return false;
  71 }
  72
  73 bool RRTS::should_break()
  74 {
  75         // decide break conditions (maybe comment some lines)
  76         //if (this->scnt_ - this->pcnt_ > 2) return true;
  77         // but continue by default
  78         return false;
  79 }
  80
  81 bool RRTS::should_continue()
  82 {
  83         // decide the stop conditions (maybe comment some lines)
  84         // it is exact opposite of `should_stop`
  85         //if (this->icnt_ > 999) return false;
  86         if (this->scnt_ > 10) return false;
  87         if (this->gf()) return false;
  88         // and reset pause counter if should continue
  89         this->pcnt_ = this->scnt_;
  90         return true;
  91 }
  92
  93 void RRTS::store_node(RRTNode n)
  94 {
  95         this->nodes().push_back(n);
  96 }
  97
  98 // RRT procedures
  99 std::tuple<bool, unsigned int, unsigned int>
 100 RRTS::collide(std::vector<std::tuple<double, double>> &poly)
 101 {
 102         for (auto &o: this->obstacles())
 103                 if (std::get<0>(::collide(poly, o.poly())))
 104                         return ::collide(poly, o.poly());
 105         return std::make_tuple(false, 0, 0);
 106 }
 107
 108 std::tuple<bool, unsigned int, unsigned int>
 109 RRTS::collide_steered_from(RRTNode &f)
 110 {
 111         auto fbc = BicycleCar();
 112         fbc.x(f.x());
 113         fbc.y(f.y());
 114         fbc.h(f.h());
 115         std::vector<std::tuple<double, double>> s;
 116         s.push_back(std::make_tuple(fbc.x(), fbc.y()));
 117         for (auto &n: this->steered()) {
 118                 auto nbc = BicycleCar();
 119                 nbc.x(n.x());
 120                 nbc.y(n.y());
 121                 nbc.h(n.h());
 122                 s.push_back(std::make_tuple(nbc.lfx(), nbc.lfy()));
 123                 s.push_back(std::make_tuple(nbc.lrx(), nbc.lry()));
 124                 s.push_back(std::make_tuple(nbc.rrx(), nbc.rry()));
 125                 s.push_back(std::make_tuple(nbc.rfx(), nbc.rfy()));
 126         }
 127         auto col = this->collide(s);
 128         auto strip_from = this->steered().size() - std::get<1>(col) / 4;
 129         if (std::get<0>(col) && strip_from > 0) {
 130                 while (strip_from-- > 0) {
 131                         this->steered().pop_back();
 132                 }
 133                 return this->collide_steered_from(f);
 134         }
 135         return col;
 136 }
 137
 138 std::tuple<bool, unsigned int, unsigned int>
 139 RRTS::collide_two_nodes(RRTNode &f, RRTNode &t)
 140 {
 141         auto fbc = BicycleCar();
 142         fbc.x(f.x());
 143         fbc.y(f.y());
 144         fbc.h(f.h());
 145         auto tbc = BicycleCar();
 146         tbc.x(f.x());
 147         tbc.y(f.y());
 148         tbc.h(f.h());
 149         std::vector<std::tuple<double, double>> p;
 150         p.push_back(std::make_tuple(fbc.lfx(), fbc.lfy()));
 151         p.push_back(std::make_tuple(fbc.lrx(), fbc.lry()));
 152         p.push_back(std::make_tuple(fbc.rrx(), fbc.rry()));
 153         p.push_back(std::make_tuple(fbc.rfx(), fbc.rfy()));
 154         p.push_back(std::make_tuple(tbc.lfx(), tbc.lfy()));
 155         p.push_back(std::make_tuple(tbc.lrx(), tbc.lry()));
 156         p.push_back(std::make_tuple(tbc.rrx(), tbc.rry()));
 157         p.push_back(std::make_tuple(tbc.rfx(), tbc.rfy()));
 158         return this->collide(p);
 159 }
 160
 161 double RRTS::cost_build(RRTNode &f, RRTNode &t)
 162 {
 163         double cost = 0;
 164         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 165         return cost;
 166 }
 167
 168 double RRTS::cost_search(RRTNode &f, RRTNode &t)
 169 {
 170         double cost = 0;
 171         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 172         return cost;
 173 }
 174
 175 void RRTS::sample()
 176 {
 177         double x = 0;
 178         double y = 0;
 179         double h = 0;
 180         switch (this->sample_dist_type()) {
 181         case 1: // uniform
 182                 x = this->udx_(this->gen_);
 183                 y = this->udy_(this->gen_);
 184                 h = this->udh_(this->gen_);
 185                 break;
 186         case 2: // uniform circle
 187         {
 188                 // see https://stackoverflow.com/questions/5837572/generate-a-random-point-within-a-circle-uniformly/50746409#50746409
 189                 double R = sqrt(
 190                         pow(
 191                                 this->nodes().front().x()
 192                                 - this->goals().front().x(),
 193                                 2
 194                         )
 195                         + pow(
 196                                 this->nodes().front().y()
 197                                 - this->goals().front().y(),
 198                                 2
 199                         )
 200                 );
 201                 double a = atan2(
 202                         this->goals().front().y() - this->nodes().front().y(),
 203                         this->goals().front().x() - this->nodes().front().x()
 204                 );
 205                 double cx = this->goals().front().x() + R/2 * cos(a);
 206                 double cy = this->goals().front().y() + R/2 * sin(a);
 207                 double r = R * sqrt(this->udx_(this->gen_));
 208                 double theta = this->udy_(this->gen_) * 2 * M_PI;
 209                 x = cx + r * cos(theta);
 210                 y = cy + r * sin(theta);
 211                 h = this->udh_(this->gen_);
 212         }
 213                 break;
 214         default: // normal
 215                 x = this->ndx_(this->gen_);
 216                 y = this->ndy_(this->gen_);
 217                 h = this->ndh_(this->gen_);
 218         }
 219         this->samples().push_back(RRTNode());
 220         this->samples().back().x(x);
 221         this->samples().back().y(y);
 222         this->samples().back().h(h);
 223 }
 224
 225 RRTNode *RRTS::nn(RRTNode &t)
 226 {
 227         RRTNode *nn = &this->nodes().front();
 228         double cost = this->cost_search(*nn, t);
 229         for (auto &f: this->nodes()) {
 230                 if (this->cost_search(f, t) < cost) {
 231                         nn = &f;
 232                         cost = this->cost_search(f, t);
 233                 }
 234         }
 235         return nn;
 236 }
 237
 238 std::vector<RRTNode *> RRTS::nv(RRTNode &t)
 239 {
 240         std::vector<RRTNode *> nv;
 241         double cost = std::min(GAMMA(this->nodes().size()), ETA);
 242         for (auto &f: this->nodes())
 243                 if (this->cost_search(f, t) < cost)
 244                         nv.push_back(&f);
 245         return nv;
 246 }
 247
 248 int cb_rs_steer(double q[4], void *user_data)
 249 {
 250         std::vector<RRTNode> *nodes = (std::vector<RRTNode> *) user_data;
 251         RRTNode *ln = nullptr;
 252         if (nodes->size() > 0)
 253                 ln = &nodes->back();
 254         nodes->push_back(RRTNode());
 255         nodes->back().x(q[0]);
 256         nodes->back().y(q[1]);
 257         nodes->back().h(q[2]);
 258         nodes->back().sp(q[3]);
 259         if (nodes->back().sp() == 0)
 260                 nodes->back().set_t(RRTNodeType::cusp);
 261         else if (ln != nullptr && sgn(ln->sp()) != sgn(nodes->back().sp()))
 262                 ln->set_t(RRTNodeType::cusp);
 263         return 0;
 264 }
 265
 266 void RRTS::steer(RRTNode &f, RRTNode &t)
 267 {
 268         this->steered().clear();
 269         double q0[] = {f.x(), f.y(), f.h()};
 270         double q1[] = {t.x(), t.y(), t.h()};
 271         ReedsSheppStateSpace rsss(this->bc.mtr());
 272         rsss.sample(q0, q1, 0.05, cb_rs_steer, &this->steered());
 273 }
 274
 275 void RRTS::steer1(RRTNode &f, RRTNode &t)
 276 {
 277     return this->steer(f, t);
 278 }
 279
 280 void RRTS::steer2(RRTNode &f, RRTNode &t)
 281 {
 282     return this->steer(f, t);
 283 }
 284
 285 void RRTS::join_steered(RRTNode *f)
 286 {
 287         while (this->steered().size() > 0) {
 288                 this->store_node(this->steered().front());
 289                 RRTNode *t = &this->nodes().back();
 290                 t->p(f);
 291                 t->c(this->cost_build(*f, *t));
 292                 this->steered().erase(this->steered().begin());
 293                 f = t;
 294         }
 295 }
 296
 297 bool RRTS::goal_found(RRTNode &f)
 298 {
 299         auto &g = this->goals().front();
 300         double cost = this->cost_build(f, g);
 301         double edist = sqrt(
 302                 pow(f.x() - g.x(), 2)
 303                 + pow(f.y() - g.y(), 2)
 304         );
 305         double adist = std::abs(f.h() - g.h());
 306         if (edist < 0.05 && adist < M_PI / 32) {
 307                 if (g.p() == nullptr || cc(f) + cost < cc(g)) {
 308                         g.p(&f);
 309                         g.c(cost);
 310                 }
 311                 return true;
 312         }
 313         return false;
 314 }
 315
 316 // RRT* procedures
 317 bool RRTS::connect()
 318 {
 319         RRTNode *t = &this->steered().front();
 320         RRTNode *f = this->nn(this->samples().back());
 321         double cost = this->cost_search(*f, *t);
 322         for (auto n: this->nv(*t)) {
 323                 if (
 324                         !std::get<0>(this->collide_two_nodes(*n, *t))
 325                         && this->cost_search(*n, *t) < cost
 326                 ) {
 327                         f = n;
 328                         cost = this->cost_search(*n, *t);
 329                 }
 330         }
 331         this->store_node(this->steered().front());
 332         t = &this->nodes().back();
 333         t->p(f);
 334         t->c(this->cost_build(*f, *t));
 335         t->set_t(RRTNodeType::connected);
 336         return true;
 337 }
 338
 339 void RRTS::rewire()
 340 {
 341         RRTNode *f = &this->nodes().back();
 342         for (auto n: this->nv(*f)) {
 343                 if (
 344                         !std::get<0>(this->collide_two_nodes(*f, *n))
 345                         && cc(*f) + this->cost_search(*f, *n) < cc(*n)
 346                 ) {
 347                         n->p(f);
 348                         n->c(this->cost_build(*f, *n));
 349                 }
 350         }
 351 }
 352
 353 // API
 354 void RRTS::init()
 355 {
 356 }
 357
 358 void RRTS::deinit()
 359 {
 360         this->nodes().clear();
 361         this->samples().clear();
 362         this->steered().clear();
 363         this->store_node(RRTNode()); // root
 364         this->icnt_ = 0;
 365         this->scnt_ = 0;
 366         this->pcnt_ = 0;
 367         this->gf_ = false;
 368 }
 369
 370 std::vector<RRTNode *> RRTS::path()
 371 {
 372         std::vector<RRTNode *> path;
 373         if (this->goals().size() == 0)
 374                 return path;
 375         RRTNode *goal = &this->goals().back();
 376         if (goal->p() == nullptr)
 377                 return path;
 378         while (goal != nullptr) {
 379                 path.push_back(goal);
 380                 goal = goal->p();
 381         }
 382         std::reverse(path.begin(), path.end());
 383         return path;
 384 }
 385
 386 bool RRTS::next()
 387 {
 388         if (this->icnt_ == 0)
 389                 this->tstart_ = std::chrono::high_resolution_clock::now();
 390         bool next = true;
 391         if (this->scnt_ > this->log_path_time_)
 392             this->log_path_cost();
 393         if (this->should_stop())
 394                 return false;
 395         if (this->samples().size() == 0) {
 396                 this->samples().push_back(RRTNode());
 397                 this->samples().back().x(this->goals().front().x());
 398                 this->samples().back().y(this->goals().front().y());
 399                 this->samples().back().h(this->goals().front().h());
 400         } else {
 401                 this->sample();
 402         }
 403         this->steer1(
 404                 *this->nn(this->samples().back()),
 405                 this->samples().back()
 406         );
 407         if (std::get<0>(this->collide_steered_from(
 408                 *this->nn(this->samples().back())
 409         )))
 410                 return next;
 411         if (!this->connect())
 412                 return next;
 413         this->rewire();
 414         unsigned scnt = this->steered().size();
 415         this->join_steered(&this->nodes().back());
 416         RRTNode *just_added = &this->nodes().back();
 417         while (scnt > 0) {
 418                 scnt--;
 419                 auto &g = this->goals().front();
 420                 this->steer2(*just_added, g);
 421                 if (std::get<0>(this->collide_steered_from(
 422                         *just_added
 423                 )))
 424                         continue;
 425                 this->join_steered(just_added);
 426                 this->gf(this->goal_found(this->nodes().back()));
 427                 just_added = just_added->p();
 428         }
 429         return next;
 430 }
 431
 432 void RRTS::set_sample_normal(
 433         double mx, double dx,
 434         double my, double dy,
 435         double mh, double dh
 436 )
 437 {
 438         this->ndx_ = std::normal_distribution<double>(mx, dx);
 439         this->ndy_ = std::normal_distribution<double>(my, dy);
 440         this->ndh_ = std::normal_distribution<double>(mh, dh);
 441 }
 442 void RRTS::set_sample_uniform(
 443         double xmin, double xmax,
 444         double ymin, double ymax,
 445         double hmin, double hmax
 446 )
 447 {
 448         this->udx_ = std::uniform_real_distribution<double>(xmin,xmax);
 449         this->udy_ = std::uniform_real_distribution<double>(ymin,ymax);
 450         this->udh_ = std::uniform_real_distribution<double>(hmin,hmax);
 451 }
 452 void RRTS::set_sample_uniform_circle()
 453 {
 454         this->udx_ = std::uniform_real_distribution<double>(0, 1);
 455         this->udy_ = std::uniform_real_distribution<double>(0, 1);
 456         this->udh_ = std::uniform_real_distribution<double>(0, 2 * M_PI);
 457 }
 458 void RRTS::set_sample(
 459         double x1, double x2,
 460         double y1, double y2,
 461         double h1, double h2
 462 )
 463 {
 464         switch (this->sample_dist_type()) {
 465         case 1: // uniform
 466                 x1 += this->nodes().front().x();
 467                 x2 += this->nodes().front().x();
 468                 y1 += this->nodes().front().y();
 469                 y2 += this->nodes().front().y();
 470                 this->set_sample_uniform(x1, x2, y1, y2, h1, h2);
 471                 break;
 472         case 2: // uniform circle
 473                 this->set_sample_uniform_circle();
 474                 break;
 475         default: // normal
 476                 this->set_sample_normal(x1, x2, y1, y2, h1, h2);
 477         }
 478 }
 479
 480 Json::Value RRTS::json()
 481 {
 482         Json::Value jvo;
 483         {
 484                 jvo["time"] = this->scnt();
 485         }
 486         {
 487                 jvo["iterations"] = this->icnt();
 488         }
 489         {
 490                 jvo["init"][0] = this->nodes().front().x();
 491                 jvo["init"][1] = this->nodes().front().y();
 492                 jvo["init"][2] = this->nodes().front().h();
 493         }
 494         {
 495                 jvo["path_cost_before_opt"] = this->path_cost_before_opt_;
 496         }
 497         {
 498                 if (this->path().size() > 0) {
 499                         jvo["cost"] = cc(*this->path().back());
 500                         jvo["entry"][0] = this->goals().front().x();
 501                         jvo["entry"][1] = this->goals().front().y();
 502                         jvo["entry"][2] = this->goals().front().h();
 503                         jvo["goal"][0] = this->goals().back().x();
 504                         jvo["goal"][1] = this->goals().back().y();
 505                         jvo["goal"][2] = this->goals().back().h();
 506                 }
 507         }
 508         {
 509                 unsigned int cu = 0;
 510                 unsigned int co = 0;
 511                 unsigned int pcnt = 0;
 512                 for (auto n: this->path()) {
 513                         jvo["path"][pcnt][0] = n->x();
 514                         jvo["path"][pcnt][1] = n->y();
 515                         jvo["path"][pcnt][2] = n->h();
 516                         if (n->t(RRTNodeType::cusp))
 517                                 cu++;
 518                         if (n->t(RRTNodeType::connected))
 519                                 co++;
 520                         pcnt++;
 521                 }
 522                 jvo["cusps-in-path"] = cu;
 523                 jvo["connecteds-in-path"] = co;
 524         }
 525         {
 526                 unsigned int gcnt = 0;
 527                 for (auto g: this->goals()) {
 528                         jvo["goals"][gcnt][0] = g.x();
 529                         jvo["goals"][gcnt][1] = g.y();
 530                         jvo["goals"][gcnt][2] = g.h();
 531                         gcnt++;
 532                 }
 533         }
 534         {
 535                 unsigned int ocnt = 0;
 536                 for (auto o: this->obstacles()) {
 537                         unsigned int ccnt = 0;
 538                         for (auto c: o.poly()) {
 539                                 jvo["obst"][ocnt][ccnt][0] = std::get<0>(c);
 540                                 jvo["obst"][ocnt][ccnt][1] = std::get<1>(c);
 541                                 ccnt++;
 542                         }
 543                         ocnt++;
 544                 }
 545         }
 546         {
 547                 jvo["nodes"] = (unsigned int) this->nodes().size();
 548         }
 549         {
 550                 unsigned int cnt = 0;
 551                 for (auto i: this->log_path_cost_)
 552                         jvo["log_path_cost"][cnt++] = i;
 553         }
 554         //{
 555         //        unsigned int ncnt = 0;
 556         //        for (auto n: this->nodes()) {
 557         //                jvo["nodes_x"][ncnt] = n.x();
 558         //                jvo["nodes_y"][ncnt] = n.y();
 559         //                //jvo["nodes_h"][ncnt] = n.h();
 560         //                ncnt++;
 561         //        }
 562         //}
 563         return jvo;
 564 }
 565
 566 void RRTS::json(Json::Value jvi)
 567 {
 568         assert(jvi["init"] != Json::nullValue);
 569         assert(jvi["goals"] != Json::nullValue);
 570         assert(jvi["obst"] != Json::nullValue);
 571
 572         this->nodes().front().x(jvi["init"][0].asDouble());
 573         this->nodes().front().y(jvi["init"][1].asDouble());
 574         this->nodes().front().h(jvi["init"][2].asDouble());
 575         {
 576             if (jvi["entry"] != Json::nullValue) {
 577                 this->entry_set = true;
 578                 this->entry.x = jvi["entry"][0].asDouble();
 579                 this->entry.y = jvi["entry"][1].asDouble();
 580                 this->entry.b = jvi["entry"][2].asDouble();
 581                 this->entry.e = jvi["entry"][3].asDouble();
 582             } else {
 583                 this->entry.x = 0.0;
 584                 this->entry.y = 0.0;
 585                 this->entry.b = 0.0;
 586                 this->entry.e = 0.0;
 587             }
 588         }
 589         {
 590                 RRTNode tmp_node;
 591                 RRTNode* gp = nullptr;
 592                 if (jvi["entry"] != Json::nullValue) {
 593                     this->entry_set = true;
 594                     this->entry.x = jvi["entry"][0].asDouble();
 595                     this->entry.y = jvi["entry"][1].asDouble();
 596                     this->entry.b = jvi["entry"][2].asDouble();
 597                     this->entry.e = jvi["entry"][3].asDouble();
 598                     tmp_node.x(this->entry.x);
 599                     tmp_node.y(this->entry.y);
 600                     tmp_node.h((this->entry.b + this->entry.e) / 2.0);
 601                     this->goals().push_back(tmp_node);
 602                     this->goals().back().p(gp);
 603                     gp = &this->goals().back();
 604                 }
 605                 for (auto g: jvi["goals"]) {
 606                         tmp_node.x(g[0].asDouble());
 607                         tmp_node.y(g[1].asDouble());
 608                         tmp_node.h(g[2].asDouble());
 609                         this->goals().push_back(tmp_node);
 610                         this->goals().back().p(gp);
 611                         gp = &this->goals().back();
 612                 }
 613                 this->goals().front().set_t(RRTNodeType::cusp);
 614                 this->goals().back().set_t(RRTNodeType::cusp);
 615         }
 616         {
 617                 Obstacle tmp_obstacle;
 618                 for (auto o: jvi["obst"]) {
 619                         tmp_obstacle.poly().clear();
 620                         for (auto c: o) {
 621                                 double tmp_x = c[0].asDouble();
 622                                 double tmp_y = c[1].asDouble();
 623                                 auto tmp_tuple = std::make_tuple(tmp_x, tmp_y);
 624                                 tmp_obstacle.poly().push_back(tmp_tuple);
 625                         }
 626                         this->obstacles().push_back(tmp_obstacle);
 627                 }
 628         }
 629         {
 630                 double edist_init_goal = sqrt(
 631                         pow(
 632                                 this->nodes().front().x()
 633                                 - this->goals().front().x(),
 634                                 2
 635                         )
 636                         + pow(
 637                                 this->nodes().front().y()
 638                                 - this->goals().front().y(),
 639                                 2
 640                         )
 641                 );
 642                 this->set_sample(
 643                         this->nodes().front().x(), edist_init_goal,
 644                         this->nodes().front().y(), edist_init_goal,
 645                         0, 2 * M_PI
 646                 );
 647         }
 648 }
 649
 650 RRTS::RRTS()
 651         : gen_(std::random_device{}())
 652 {
 653         this->goals().reserve(100);
 654         this->nodes().reserve(4000000);
 655         this->samples().reserve(1000);
 656         this->steered().reserve(20000);
 657         this->store_node(RRTNode()); // root
 658 }
 659
 660 double cc(RRTNode &t)
 661 {
 662         RRTNode *n = &t;
 663         double cost = 0;
 664         while (n != nullptr) {
 665                 cost += n->c();
 666                 n = n->p();
 667         }
 668         return cost;
 669 }