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         if (this->gf())
  48                 this->log_path_cost_.push_back(cc(this->goals().front()));
  49         else
  50                 this->log_path_cost_.push_back(0);
  51 }
  52
  53 bool RRTS::should_stop()
  54 {
  55         // the following counters must be updated, do not comment
  56         this->icnt_++;
  57         this->elapsed();
  58         // current iteration stop conditions
  59         if (this->should_finish()) return true;
  60         if (this->should_break()) return true;
  61         // but continue by default
  62         return false;
  63 }
  64
  65 bool RRTS::should_finish()
  66 {
  67         // decide finish conditions (maybe comment some lines)
  68         //if (this->icnt_ > 999) return true;
  69         if (this->scnt_ > 10) return true;
  70         if (this->gf()) return true;
  71         // but continue by default
  72         return false;
  73 }
  74
  75 bool RRTS::should_break()
  76 {
  77         // decide break conditions (maybe comment some lines)
  78         //if (this->scnt_ - this->pcnt_ > 2) return true;
  79         // but continue by default
  80         return false;
  81 }
  82
  83 bool RRTS::should_continue()
  84 {
  85         // decide the stop conditions (maybe comment some lines)
  86         // it is exact opposite of `should_stop`
  87         //if (this->icnt_ > 999) return false;
  88         if (this->scnt_ > 10) return false;
  89         if (this->gf()) return false;
  90         // and reset pause counter if should continue
  91         this->pcnt_ = this->scnt_;
  92         return true;
  93 }
  94
  95 void RRTS::store_node(RRTNode n)
  96 {
  97         this->nodes().push_back(n);
  98 }
  99
 100 // RRT procedures
 101 std::tuple<bool, unsigned int, unsigned int>
 102 RRTS::collide(std::vector<std::tuple<double, double>> &poly)
 103 {
 104         for (auto &o: this->obstacles())
 105                 if (std::get<0>(::collide(poly, o.poly())))
 106                         return ::collide(poly, o.poly());
 107         return std::make_tuple(false, 0, 0);
 108 }
 109
 110 std::tuple<bool, unsigned int, unsigned int>
 111 RRTS::collide_steered_from(RRTNode &f)
 112 {
 113         auto fbc = BicycleCar();
 114         fbc.x(f.x());
 115         fbc.y(f.y());
 116         fbc.h(f.h());
 117         std::vector<std::tuple<double, double>> s;
 118         s.push_back(std::make_tuple(fbc.x(), fbc.y()));
 119         for (auto &n: this->steered()) {
 120                 auto nbc = BicycleCar();
 121                 nbc.x(n.x());
 122                 nbc.y(n.y());
 123                 nbc.h(n.h());
 124                 s.push_back(std::make_tuple(nbc.lfx(), nbc.lfy()));
 125                 s.push_back(std::make_tuple(nbc.lrx(), nbc.lry()));
 126                 s.push_back(std::make_tuple(nbc.rrx(), nbc.rry()));
 127                 s.push_back(std::make_tuple(nbc.rfx(), nbc.rfy()));
 128         }
 129         auto col = this->collide(s);
 130         auto strip_from = this->steered().size() - std::get<1>(col) / 4;
 131         if (std::get<0>(col) && strip_from > 0) {
 132                 while (strip_from-- > 0) {
 133                         this->steered().pop_back();
 134                 }
 135                 return this->collide_steered_from(f);
 136         }
 137         return col;
 138 }
 139
 140 std::tuple<bool, unsigned int, unsigned int>
 141 RRTS::collide_two_nodes(RRTNode &f, RRTNode &t)
 142 {
 143         auto fbc = BicycleCar();
 144         fbc.x(f.x());
 145         fbc.y(f.y());
 146         fbc.h(f.h());
 147         auto tbc = BicycleCar();
 148         tbc.x(f.x());
 149         tbc.y(f.y());
 150         tbc.h(f.h());
 151         std::vector<std::tuple<double, double>> p;
 152         p.push_back(std::make_tuple(fbc.lfx(), fbc.lfy()));
 153         p.push_back(std::make_tuple(fbc.lrx(), fbc.lry()));
 154         p.push_back(std::make_tuple(fbc.rrx(), fbc.rry()));
 155         p.push_back(std::make_tuple(fbc.rfx(), fbc.rfy()));
 156         p.push_back(std::make_tuple(tbc.lfx(), tbc.lfy()));
 157         p.push_back(std::make_tuple(tbc.lrx(), tbc.lry()));
 158         p.push_back(std::make_tuple(tbc.rrx(), tbc.rry()));
 159         p.push_back(std::make_tuple(tbc.rfx(), tbc.rfy()));
 160         return this->collide(p);
 161 }
 162
 163 double RRTS::cost_build(RRTNode &f, RRTNode &t)
 164 {
 165         double cost = 0;
 166         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 167         return cost;
 168 }
 169
 170 double RRTS::cost_search(RRTNode &f, RRTNode &t)
 171 {
 172         double cost = 0;
 173         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 174         return cost;
 175 }
 176
 177 void RRTS::sample()
 178 {
 179         double x = 0;
 180         double y = 0;
 181         double h = 0;
 182         switch (this->sample_dist_type()) {
 183         case 1: // uniform
 184                 x = this->udx_(this->gen_);
 185                 y = this->udy_(this->gen_);
 186                 h = this->udh_(this->gen_);
 187                 break;
 188         case 2: // uniform circle
 189         {
 190                 // see https://stackoverflow.com/questions/5837572/generate-a-random-point-within-a-circle-uniformly/50746409#50746409
 191                 double R = sqrt(
 192                         pow(
 193                                 this->nodes().front().x()
 194                                 - this->goals().front().x(),
 195                                 2
 196                         )
 197                         + pow(
 198                                 this->nodes().front().y()
 199                                 - this->goals().front().y(),
 200                                 2
 201                         )
 202                 );
 203                 double a = atan2(
 204                         this->goals().front().y() - this->nodes().front().y(),
 205                         this->goals().front().x() - this->nodes().front().x()
 206                 );
 207                 double cx = this->goals().front().x() + R/2 * cos(a);
 208                 double cy = this->goals().front().y() + R/2 * sin(a);
 209                 double r = R * sqrt(this->udx_(this->gen_));
 210                 double theta = this->udy_(this->gen_) * 2 * M_PI;
 211                 x = cx + r * cos(theta);
 212                 y = cy + r * sin(theta);
 213                 h = this->udh_(this->gen_);
 214         }
 215                 break;
 216         default: // normal
 217                 x = this->ndx_(this->gen_);
 218                 y = this->ndy_(this->gen_);
 219                 h = this->ndh_(this->gen_);
 220         }
 221         this->samples().push_back(RRTNode());
 222         this->samples().back().x(x);
 223         this->samples().back().y(y);
 224         this->samples().back().h(h);
 225 }
 226
 227 RRTNode *RRTS::nn(RRTNode &t)
 228 {
 229         RRTNode *nn = &this->nodes().front();
 230         double cost = this->cost_search(*nn, t);
 231         for (auto &f: this->nodes()) {
 232                 if (this->cost_search(f, t) < cost) {
 233                         nn = &f;
 234                         cost = this->cost_search(f, t);
 235                 }
 236         }
 237         return nn;
 238 }
 239
 240 std::vector<RRTNode *> RRTS::nv(RRTNode &t)
 241 {
 242         std::vector<RRTNode *> nv;
 243         double cost = std::min(GAMMA(this->nodes().size()), ETA);
 244         for (auto &f: this->nodes())
 245                 if (this->cost_search(f, t) < cost)
 246                         nv.push_back(&f);
 247         return nv;
 248 }
 249
 250 int cb_rs_steer(double q[4], void *user_data)
 251 {
 252         std::vector<RRTNode> *nodes = (std::vector<RRTNode> *) user_data;
 253         RRTNode *ln = nullptr;
 254         if (nodes->size() > 0)
 255                 ln = &nodes->back();
 256         nodes->push_back(RRTNode());
 257         nodes->back().x(q[0]);
 258         nodes->back().y(q[1]);
 259         nodes->back().h(q[2]);
 260         nodes->back().sp(q[3]);
 261         if (nodes->back().sp() == 0)
 262                 nodes->back().set_t(RRTNodeType::cusp);
 263         else if (ln != nullptr && sgn(ln->sp()) != sgn(nodes->back().sp()))
 264                 ln->set_t(RRTNodeType::cusp);
 265         return 0;
 266 }
 267
 268 void RRTS::steer(RRTNode &f, RRTNode &t)
 269 {
 270         this->steered().clear();
 271         double q0[] = {f.x(), f.y(), f.h()};
 272         double q1[] = {t.x(), t.y(), t.h()};
 273         ReedsSheppStateSpace rsss(this->bc.mtr());
 274         rsss.sample(q0, q1, 0.5, cb_rs_steer, &this->steered());
 275 }
 276
 277 void RRTS::join_steered(RRTNode *f)
 278 {
 279         while (this->steered().size() > 0) {
 280                 this->store_node(this->steered().front());
 281                 RRTNode *t = &this->nodes().back();
 282                 t->p(f);
 283                 t->c(this->cost_build(*f, *t));
 284                 this->steered().erase(this->steered().begin());
 285                 f = t;
 286         }
 287 }
 288
 289 bool RRTS::goal_found(RRTNode &f)
 290 {
 291         auto &g = this->goals().front();
 292         double cost = this->cost_build(f, g);
 293         double edist = sqrt(
 294                 pow(f.x() - g.x(), 2)
 295                 + pow(f.y() - g.y(), 2)
 296         );
 297         double adist = std::abs(f.h() - g.h());
 298         if (edist < 0.05 && adist < M_PI / 32) {
 299                 if (g.p() == nullptr || cc(f) + cost < cc(g)) {
 300                         g.p(&f);
 301                         g.c(cost);
 302                 }
 303                 return true;
 304         }
 305         return false;
 306 }
 307
 308 // RRT* procedures
 309 bool RRTS::connect()
 310 {
 311         RRTNode *t = &this->steered().front();
 312         RRTNode *f = this->nn(this->samples().back());
 313         double cost = this->cost_search(*f, *t);
 314         for (auto n: this->nv(*t)) {
 315                 if (
 316                         !std::get<0>(this->collide_two_nodes(*n, *t))
 317                         && this->cost_search(*n, *t) < cost
 318                 ) {
 319                         f = n;
 320                         cost = this->cost_search(*n, *t);
 321                 }
 322         }
 323         this->store_node(this->steered().front());
 324         t = &this->nodes().back();
 325         t->p(f);
 326         t->c(this->cost_build(*f, *t));
 327         t->set_t(RRTNodeType::connected);
 328         return true;
 329 }
 330
 331 void RRTS::rewire()
 332 {
 333         RRTNode *f = &this->nodes().back();
 334         for (auto n: this->nv(*f)) {
 335                 if (
 336                         !std::get<0>(this->collide_two_nodes(*f, *n))
 337                         && cc(*f) + this->cost_search(*f, *n) < cc(*n)
 338                 ) {
 339                         n->p(f);
 340                         n->c(this->cost_build(*f, *n));
 341                 }
 342         }
 343 }
 344
 345 // API
 346 void RRTS::init()
 347 {
 348 }
 349
 350 void RRTS::deinit()
 351 {
 352         this->nodes().clear();
 353         this->samples().clear();
 354         this->steered().clear();
 355         this->store_node(RRTNode()); // root
 356         this->icnt_ = 0;
 357         this->scnt_ = 0;
 358         this->pcnt_ = 0;
 359         this->gf_ = false;
 360 }
 361
 362 std::vector<RRTNode *> RRTS::path()
 363 {
 364         std::vector<RRTNode *> path;
 365         if (this->goals().size() == 0)
 366                 return path;
 367         RRTNode *goal = &this->goals().front();
 368         if (goal->p() == nullptr)
 369                 return path;
 370         while (goal != nullptr) {
 371                 path.push_back(goal);
 372                 goal = goal->p();
 373         }
 374         std::reverse(path.begin(), path.end());
 375         return path;
 376 }
 377
 378 bool RRTS::next()
 379 {
 380         if (this->icnt_ == 0)
 381                 this->tstart_ = std::chrono::high_resolution_clock::now();
 382         bool next = true;
 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                 if (this->path().size() > 0) {
 486                         jvo["cost"] = cc(*this->path().back());
 487                         jvo["goal"][0] = this->path().back()->x();
 488                         jvo["goal"][1] = this->path().back()->y();
 489                         jvo["goal"][2] = this->path().back()->h();
 490                 }
 491         }
 492         {
 493                 unsigned int cu = 0;
 494                 unsigned int co = 0;
 495                 unsigned int pcnt = 0;
 496                 for (auto n: this->path()) {
 497                         jvo["path"][pcnt][0] = n->x();
 498                         jvo["path"][pcnt][1] = n->y();
 499                         jvo["path"][pcnt][2] = n->h();
 500                         if (n->t(RRTNodeType::cusp))
 501                                 cu++;
 502                         if (n->t(RRTNodeType::connected))
 503                                 co++;
 504                         pcnt++;
 505                 }
 506                 jvo["cusps-in-path"] = cu;
 507                 jvo["connecteds-in-path"] = co;
 508         }
 509         {
 510                 unsigned int gcnt = 0;
 511                 for (auto g: this->goals()) {
 512                         jvo["goals"][gcnt][0] = g.x();
 513                         jvo["goals"][gcnt][1] = g.y();
 514                         jvo["goals"][gcnt][2] = g.h();
 515                         gcnt++;
 516                 }
 517         }
 518         {
 519                 unsigned int ocnt = 0;
 520                 for (auto o: this->obstacles()) {
 521                         unsigned int ccnt = 0;
 522                         for (auto c: o.poly()) {
 523                                 jvo["obst"][ocnt][ccnt][0] = std::get<0>(c);
 524                                 jvo["obst"][ocnt][ccnt][1] = std::get<1>(c);
 525                                 ccnt++;
 526                         }
 527                         ocnt++;
 528                 }
 529         }
 530         {
 531                 jvo["nodes"] = (unsigned int) this->nodes().size();
 532         }
 533         {
 534                 unsigned int cnt = 0;
 535                 for (auto i: this->log_path_cost_)
 536                         jvo["log_path_cost"][cnt++] = i;
 537         }
 538         //{
 539         //        unsigned int ncnt = 0;
 540         //        for (auto n: this->nodes()) {
 541         //                jvo["nodes_x"][ncnt] = n.x();
 542         //                jvo["nodes_y"][ncnt] = n.y();
 543         //                //jvo["nodes_h"][ncnt] = n.h();
 544         //                ncnt++;
 545         //        }
 546         //}
 547         return jvo;
 548 }
 549
 550 void RRTS::json(Json::Value jvi)
 551 {
 552         assert(jvi["init"] != Json::nullValue);
 553         assert(jvi["goal"] != Json::nullValue);
 554         assert(jvi["goals"] != Json::nullValue);
 555         assert(jvi["obst"] != Json::nullValue);
 556
 557         this->nodes().front().x(jvi["init"][0].asDouble());
 558         this->nodes().front().y(jvi["init"][1].asDouble());
 559         this->nodes().front().h(jvi["init"][2].asDouble());
 560         {
 561                 RRTNode tmp_node;
 562                 tmp_node.x(jvi["goal"][0].asDouble());
 563                 tmp_node.y(jvi["goal"][1].asDouble());
 564                 tmp_node.h(jvi["goal"][2].asDouble());
 565                 this->goals().push_back(tmp_node);
 566                 for (auto g: jvi["goals"]) {
 567                         tmp_node.x(g[0].asDouble());
 568                         tmp_node.y(g[1].asDouble());
 569                         tmp_node.h(g[2].asDouble());
 570                         this->goals().push_back(tmp_node);
 571                 }
 572         }
 573         {
 574                 Obstacle tmp_obstacle;
 575                 for (auto o: jvi["obst"]) {
 576                         tmp_obstacle.poly().clear();
 577                         for (auto c: o) {
 578                                 double tmp_x = c[0].asDouble();
 579                                 double tmp_y = c[1].asDouble();
 580                                 auto tmp_tuple = std::make_tuple(tmp_x, tmp_y);
 581                                 tmp_obstacle.poly().push_back(tmp_tuple);
 582                         }
 583                         this->obstacles().push_back(tmp_obstacle);
 584                 }
 585         }
 586         {
 587                 double edist_init_goal = sqrt(
 588                         pow(
 589                                 this->nodes().front().x()
 590                                 - this->goals().front().x(),
 591                                 2
 592                         )
 593                         + pow(
 594                                 this->nodes().front().y()
 595                                 - this->goals().front().y(),
 596                                 2
 597                         )
 598                 );
 599                 this->set_sample(
 600                         this->nodes().front().x(), edist_init_goal,
 601                         this->nodes().front().y(), edist_init_goal,
 602                         0, 2 * M_PI
 603                 );
 604         }
 605 }
 606
 607 RRTS::RRTS()
 608         : gen_(std::random_device{}())
 609 {
 610         this->goals().reserve(100);
 611         this->nodes().reserve(4000000);
 612         this->samples().reserve(1000);
 613         this->steered().reserve(20000);
 614         this->store_node(RRTNode()); // root
 615 }
 616
 617 double cc(RRTNode &t)
 618 {
 619         RRTNode *n = &t;
 620         double cost = 0;
 621         while (n != nullptr) {
 622                 cost += n->c();
 623                 n = n->p();
 624         }
 625         return cost;
 626 }