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, 0.5, cb_rs_steer, &this->steered());
 273 }
 274
 275 void RRTS::join_steered(RRTNode *f)
 276 {
 277         while (this->steered().size() > 0) {
 278                 this->store_node(this->steered().front());
 279                 RRTNode *t = &this->nodes().back();
 280                 t->p(f);
 281                 t->c(this->cost_build(*f, *t));
 282                 this->steered().erase(this->steered().begin());
 283                 f = t;
 284         }
 285 }
 286
 287 bool RRTS::goal_found(RRTNode &f)
 288 {
 289         auto &g = this->goals().front();
 290         double cost = this->cost_build(f, g);
 291         double edist = sqrt(
 292                 pow(f.x() - g.x(), 2)
 293                 + pow(f.y() - g.y(), 2)
 294         );
 295         double adist = std::abs(f.h() - g.h());
 296         if (edist < 0.05 && adist < M_PI / 32) {
 297                 if (g.p() == nullptr || cc(f) + cost < cc(g)) {
 298                         g.p(&f);
 299                         g.c(cost);
 300                 }
 301                 return true;
 302         }
 303         return false;
 304 }
 305
 306 // RRT* procedures
 307 bool RRTS::connect()
 308 {
 309         RRTNode *t = &this->steered().front();
 310         RRTNode *f = this->nn(this->samples().back());
 311         double cost = this->cost_search(*f, *t);
 312         for (auto n: this->nv(*t)) {
 313                 if (
 314                         !std::get<0>(this->collide_two_nodes(*n, *t))
 315                         && this->cost_search(*n, *t) < cost
 316                 ) {
 317                         f = n;
 318                         cost = this->cost_search(*n, *t);
 319                 }
 320         }
 321         this->store_node(this->steered().front());
 322         t = &this->nodes().back();
 323         t->p(f);
 324         t->c(this->cost_build(*f, *t));
 325         t->set_t(RRTNodeType::connected);
 326         return true;
 327 }
 328
 329 void RRTS::rewire()
 330 {
 331         RRTNode *f = &this->nodes().back();
 332         for (auto n: this->nv(*f)) {
 333                 if (
 334                         !std::get<0>(this->collide_two_nodes(*f, *n))
 335                         && cc(*f) + this->cost_search(*f, *n) < cc(*n)
 336                 ) {
 337                         n->p(f);
 338                         n->c(this->cost_build(*f, *n));
 339                 }
 340         }
 341 }
 342
 343 // API
 344 void RRTS::init()
 345 {
 346 }
 347
 348 void RRTS::deinit()
 349 {
 350         this->nodes().clear();
 351         this->samples().clear();
 352         this->steered().clear();
 353         this->store_node(RRTNode()); // root
 354         this->icnt_ = 0;
 355         this->scnt_ = 0;
 356         this->pcnt_ = 0;
 357         this->gf_ = false;
 358 }
 359
 360 std::vector<RRTNode *> RRTS::path()
 361 {
 362         std::vector<RRTNode *> path;
 363         if (this->goals().size() == 0)
 364                 return path;
 365         RRTNode *goal = &this->goals().front();
 366         if (goal->p() == nullptr)
 367                 return path;
 368         while (goal != nullptr) {
 369                 path.push_back(goal);
 370                 goal = goal->p();
 371         }
 372         std::reverse(path.begin(), path.end());
 373         return path;
 374 }
 375
 376 bool RRTS::next()
 377 {
 378         if (this->icnt_ == 0)
 379                 this->tstart_ = std::chrono::high_resolution_clock::now();
 380         bool next = true;
 381         if (this->scnt_ > this->log_path_time_)
 382             this->log_path_cost();
 383         if (this->should_stop())
 384                 return false;
 385         if (this->samples().size() == 0) {
 386                 this->samples().push_back(RRTNode());
 387                 this->samples().back().x(this->goals().front().x());
 388                 this->samples().back().y(this->goals().front().y());
 389                 this->samples().back().h(this->goals().front().h());
 390         } else {
 391                 this->sample();
 392         }
 393         this->steer(
 394                 *this->nn(this->samples().back()),
 395                 this->samples().back()
 396         );
 397         if (std::get<0>(this->collide_steered_from(
 398                 *this->nn(this->samples().back())
 399         )))
 400                 return next;
 401         if (!this->connect())
 402                 return next;
 403         this->rewire();
 404         unsigned scnt = this->steered().size();
 405         this->join_steered(&this->nodes().back());
 406         RRTNode *just_added = &this->nodes().back();
 407         while (scnt > 0) {
 408                 scnt--;
 409                 auto &g = this->goals().front();
 410                 this->steer(*just_added, g);
 411                 if (std::get<0>(this->collide_steered_from(
 412                         *just_added
 413                 )))
 414                         continue;
 415                 this->join_steered(just_added);
 416                 this->gf(this->goal_found(this->nodes().back()));
 417                 just_added = just_added->p();
 418         }
 419         return next;
 420 }
 421
 422 void RRTS::set_sample_normal(
 423         double mx, double dx,
 424         double my, double dy,
 425         double mh, double dh
 426 )
 427 {
 428         this->ndx_ = std::normal_distribution<double>(mx, dx);
 429         this->ndy_ = std::normal_distribution<double>(my, dy);
 430         this->ndh_ = std::normal_distribution<double>(mh, dh);
 431 }
 432 void RRTS::set_sample_uniform(
 433         double xmin, double xmax,
 434         double ymin, double ymax,
 435         double hmin, double hmax
 436 )
 437 {
 438         this->udx_ = std::uniform_real_distribution<double>(xmin,xmax);
 439         this->udy_ = std::uniform_real_distribution<double>(ymin,ymax);
 440         this->udh_ = std::uniform_real_distribution<double>(hmin,hmax);
 441 }
 442 void RRTS::set_sample_uniform_circle()
 443 {
 444         this->udx_ = std::uniform_real_distribution<double>(0, 1);
 445         this->udy_ = std::uniform_real_distribution<double>(0, 1);
 446         this->udh_ = std::uniform_real_distribution<double>(0, 2 * M_PI);
 447 }
 448 void RRTS::set_sample(
 449         double x1, double x2,
 450         double y1, double y2,
 451         double h1, double h2
 452 )
 453 {
 454         switch (this->sample_dist_type()) {
 455         case 1: // uniform
 456                 x1 += this->nodes().front().x();
 457                 x2 += this->nodes().front().x();
 458                 y1 += this->nodes().front().y();
 459                 y2 += this->nodes().front().y();
 460                 this->set_sample_uniform(x1, x2, y1, y2, h1, h2);
 461                 break;
 462         case 2: // uniform circle
 463                 this->set_sample_uniform_circle();
 464                 break;
 465         default: // normal
 466                 this->set_sample_normal(x1, x2, y1, y2, h1, h2);
 467         }
 468 }
 469
 470 Json::Value RRTS::json()
 471 {
 472         Json::Value jvo;
 473         {
 474                 jvo["time"] = this->scnt();
 475         }
 476         {
 477                 jvo["iterations"] = this->icnt();
 478         }
 479         {
 480                 jvo["init"][0] = this->nodes().front().x();
 481                 jvo["init"][1] = this->nodes().front().y();
 482                 jvo["init"][2] = this->nodes().front().h();
 483         }
 484         {
 485                 jvo["path_cost_before_opt"] = this->path_cost_before_opt_;
 486         }
 487         {
 488                 if (this->path().size() > 0) {
 489                         jvo["cost"] = cc(*this->path().back());
 490                         jvo["goal"][0] = this->path().back()->x();
 491                         jvo["goal"][1] = this->path().back()->y();
 492                         jvo["goal"][2] = this->path().back()->h();
 493                 }
 494         }
 495         {
 496                 unsigned int cu = 0;
 497                 unsigned int co = 0;
 498                 unsigned int pcnt = 0;
 499                 for (auto n: this->path()) {
 500                         jvo["path"][pcnt][0] = n->x();
 501                         jvo["path"][pcnt][1] = n->y();
 502                         jvo["path"][pcnt][2] = n->h();
 503                         if (n->t(RRTNodeType::cusp))
 504                                 cu++;
 505                         if (n->t(RRTNodeType::connected))
 506                                 co++;
 507                         pcnt++;
 508                 }
 509                 jvo["cusps-in-path"] = cu;
 510                 jvo["connecteds-in-path"] = co;
 511         }
 512         {
 513                 unsigned int gcnt = 0;
 514                 for (auto g: this->goals()) {
 515                         jvo["goals"][gcnt][0] = g.x();
 516                         jvo["goals"][gcnt][1] = g.y();
 517                         jvo["goals"][gcnt][2] = g.h();
 518                         gcnt++;
 519                 }
 520         }
 521         {
 522                 unsigned int ocnt = 0;
 523                 for (auto o: this->obstacles()) {
 524                         unsigned int ccnt = 0;
 525                         for (auto c: o.poly()) {
 526                                 jvo["obst"][ocnt][ccnt][0] = std::get<0>(c);
 527                                 jvo["obst"][ocnt][ccnt][1] = std::get<1>(c);
 528                                 ccnt++;
 529                         }
 530                         ocnt++;
 531                 }
 532         }
 533         {
 534                 jvo["nodes"] = (unsigned int) this->nodes().size();
 535         }
 536         {
 537                 unsigned int cnt = 0;
 538                 for (auto i: this->log_path_cost_)
 539                         jvo["log_path_cost"][cnt++] = i;
 540         }
 541         //{
 542         //        unsigned int ncnt = 0;
 543         //        for (auto n: this->nodes()) {
 544         //                jvo["nodes_x"][ncnt] = n.x();
 545         //                jvo["nodes_y"][ncnt] = n.y();
 546         //                //jvo["nodes_h"][ncnt] = n.h();
 547         //                ncnt++;
 548         //        }
 549         //}
 550         return jvo;
 551 }
 552
 553 void RRTS::json(Json::Value jvi)
 554 {
 555         assert(jvi["init"] != Json::nullValue);
 556         assert(jvi["goals"] != Json::nullValue);
 557         assert(jvi["obst"] != Json::nullValue);
 558
 559         this->nodes().front().x(jvi["init"][0].asDouble());
 560         this->nodes().front().y(jvi["init"][1].asDouble());
 561         this->nodes().front().h(jvi["init"][2].asDouble());
 562         {
 563                 RRTNode tmp_node;
 564                 RRTNode* gp = nullptr;
 565                 for (auto g: jvi["goals"]) {
 566                         tmp_node.x(g[0].asDouble());
 567                         tmp_node.y(g[1].asDouble());
 568                         tmp_node.h(g[2].asDouble());
 569                         this->goals().push_back(tmp_node);
 570                         this->goals().back().p(gp);
 571                         gp = &this->goals().back();
 572                 }
 573                 this->goals().front().set_t(RRTNodeType::cusp);
 574                 this->goals().back().set_t(RRTNodeType::cusp);
 575         }
 576         {
 577                 Obstacle tmp_obstacle;
 578                 for (auto o: jvi["obst"]) {
 579                         tmp_obstacle.poly().clear();
 580                         for (auto c: o) {
 581                                 double tmp_x = c[0].asDouble();
 582                                 double tmp_y = c[1].asDouble();
 583                                 auto tmp_tuple = std::make_tuple(tmp_x, tmp_y);
 584                                 tmp_obstacle.poly().push_back(tmp_tuple);
 585                         }
 586                         this->obstacles().push_back(tmp_obstacle);
 587                 }
 588         }
 589         {
 590                 double edist_init_goal = sqrt(
 591                         pow(
 592                                 this->nodes().front().x()
 593                                 - this->goals().front().x(),
 594                                 2
 595                         )
 596                         + pow(
 597                                 this->nodes().front().y()
 598                                 - this->goals().front().y(),
 599                                 2
 600                         )
 601                 );
 602                 this->set_sample(
 603                         this->nodes().front().x(), edist_init_goal,
 604                         this->nodes().front().y(), edist_init_goal,
 605                         0, 2 * M_PI
 606                 );
 607         }
 608 }
 609
 610 RRTS::RRTS()
 611         : gen_(std::random_device{}())
 612 {
 613         this->goals().reserve(100);
 614         this->nodes().reserve(4000000);
 615         this->samples().reserve(1000);
 616         this->steered().reserve(20000);
 617         this->store_node(RRTNode()); // root
 618 }
 619
 620 double cc(RRTNode &t)
 621 {
 622         RRTNode *n = &t;
 623         double cost = 0;
 624         while (n != nullptr) {
 625                 cost += n->c();
 626                 n = n->p();
 627         }
 628         return cost;
 629 }