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) : BicycleCar(bc)
  15 {
  16 }
  17
  18 Obstacle::Obstacle()
  19 {
  20 }
  21
  22 double RRTS::elapsed()
  23 {
  24         std::chrono::duration<double> dt;
  25         dt = std::chrono::duration_cast<std::chrono::duration<double>>(
  26                 std::chrono::high_resolution_clock::now()
  27                 - this->tstart_
  28         );
  29         this->scnt_ = dt.count();
  30         return this->scnt_;
  31 }
  32
  33 bool RRTS::should_stop()
  34 {
  35         // the following counters must be updated, do not comment
  36         this->icnt_++;
  37         this->elapsed();
  38         // current iteration stop conditions
  39         if (this->should_finish()) return true;
  40         if (this->should_break()) return true;
  41         // but continue by default
  42         return false;
  43 }
  44
  45 bool RRTS::should_finish()
  46 {
  47         // decide finish conditions (maybe comment some lines)
  48         //if (this->icnt_ > 999) return true;
  49         if (this->scnt_ > 5) return true;
  50         if (this->gf()) return true;
  51         // but continue by default
  52         return false;
  53 }
  54
  55 bool RRTS::should_break()
  56 {
  57         // decide break conditions (maybe comment some lines)
  58         //if (this->scnt_ - this->pcnt_ > 2) return true;
  59         // but continue by default
  60         return false;
  61 }
  62
  63 bool RRTS::should_continue()
  64 {
  65         // decide the stop conditions (maybe comment some lines)
  66         // it is exact opposite of `should_stop`
  67         //if (this->icnt_ > 999) return false;
  68         if (this->scnt_ > 10) return false;
  69         if (this->gf()) return false;
  70         // and reset pause counter if should continue
  71         this->pcnt_ = this->scnt_;
  72         return true;
  73 }
  74
  75 void RRTS::store_node(RRTNode n)
  76 {
  77         this->nodes().push_back(n);
  78 }
  79
  80 // RRT procedures
  81 std::tuple<bool, unsigned int, unsigned int>
  82 RRTS::collide(std::vector<std::tuple<double, double>> &poly)
  83 {
  84         for (auto &o: this->obstacles())
  85                 if (std::get<0>(::collide(poly, o.poly())))
  86                         return ::collide(poly, o.poly());
  87         return std::make_tuple(false, 0, 0);
  88 }
  89
  90 std::tuple<bool, unsigned int, unsigned int>
  91 RRTS::collide_steered_from(RRTNode &f)
  92 {
  93         std::vector<std::tuple<double, double>> s;
  94         s.push_back(std::make_tuple(f.x(), f.y()));
  95         for (auto &n: this->steered()) {
  96                 s.push_back(std::make_tuple(n.lfx(), n.lfy()));
  97                 s.push_back(std::make_tuple(n.lrx(), n.lry()));
  98                 s.push_back(std::make_tuple(n.rrx(), n.rry()));
  99                 s.push_back(std::make_tuple(n.rfx(), n.rfy()));
 100         }
 101         auto col = this->collide(s);
 102         auto strip_from = this->steered().size() - std::get<1>(col) / 4;
 103         if (std::get<0>(col) && strip_from > 0) {
 104                 while (strip_from-- > 0) {
 105                         this->steered().pop_back();
 106                 }
 107                 return this->collide_steered_from(f);
 108         }
 109         return col;
 110 }
 111
 112 std::tuple<bool, unsigned int, unsigned int>
 113 RRTS::collide_two_nodes(RRTNode &f, RRTNode &t)
 114 {
 115         std::vector<std::tuple<double, double>> p;
 116         p.push_back(std::make_tuple(f.lfx(), f.lfy()));
 117         p.push_back(std::make_tuple(f.lrx(), f.lry()));
 118         p.push_back(std::make_tuple(f.rrx(), f.rry()));
 119         p.push_back(std::make_tuple(f.rfx(), f.rfy()));
 120         p.push_back(std::make_tuple(t.lfx(), t.lfy()));
 121         p.push_back(std::make_tuple(t.lrx(), t.lry()));
 122         p.push_back(std::make_tuple(t.rrx(), t.rry()));
 123         p.push_back(std::make_tuple(t.rfx(), t.rfy()));
 124         return this->collide(p);
 125 }
 126
 127 double RRTS::cost_build(RRTNode &f, RRTNode &t)
 128 {
 129         double cost = 0;
 130         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 131         return cost;
 132 }
 133
 134 double RRTS::cost_search(RRTNode &f, RRTNode &t)
 135 {
 136         double cost = 0;
 137         cost = sqrt(pow(t.y() - f.y(), 2) + pow(t.x() - f.x(), 2));
 138         return cost;
 139 }
 140
 141 void RRTS::sample()
 142 {
 143         double x = this->ndx_(this->gen_);
 144         double y = this->ndy_(this->gen_);
 145         double h = this->ndh_(this->gen_);
 146         this->samples().push_back(RRTNode());
 147         this->samples().back().x(x);
 148         this->samples().back().y(y);
 149         this->samples().back().h(h);
 150 }
 151
 152 RRTNode *RRTS::nn(RRTNode &t)
 153 {
 154         RRTNode *nn = &this->nodes().front();
 155         double cost = this->cost_search(*nn, t);
 156         for (auto &f: this->nodes()) {
 157                 if (this->cost_search(f, t) < cost) {
 158                         nn = &f;
 159                         cost = this->cost_search(f, t);
 160                 }
 161         }
 162         return nn;
 163 }
 164
 165 std::vector<RRTNode *> RRTS::nv(RRTNode &t)
 166 {
 167         std::vector<RRTNode *> nv;
 168         double cost = std::min(GAMMA(this->nodes().size()), ETA);
 169         for (auto &f: this->nodes())
 170                 if (this->cost_search(f, t) < cost)
 171                         nv.push_back(&f);
 172         return nv;
 173 }
 174
 175 int cb_rs_steer(double q[4], void *user_data)
 176 {
 177         std::vector<RRTNode> *nodes = (std::vector<RRTNode> *) user_data;
 178         RRTNode *ln = nullptr;
 179         if (nodes->size() > 0)
 180                 ln = &nodes->back();
 181         nodes->push_back(RRTNode());
 182         nodes->back().x(q[0]);
 183         nodes->back().y(q[1]);
 184         nodes->back().h(q[2]);
 185         nodes->back().sp(q[3]);
 186         if (nodes->back().sp() == 0)
 187                 nodes->back().set_t(RRTNodeType::cusp);
 188         else if (ln != nullptr && sgn(ln->sp()) != sgn(nodes->back().sp()))
 189                 ln->set_t(RRTNodeType::cusp);
 190         return 0;
 191 }
 192
 193 void RRTS::steer(RRTNode &f, RRTNode &t)
 194 {
 195         this->steered().clear();
 196         double q0[] = {f.x(), f.y(), f.h()};
 197         double q1[] = {t.x(), t.y(), t.h()};
 198         ReedsSheppStateSpace rsss(f.mtr());
 199         rsss.sample(q0, q1, 0.5, cb_rs_steer, &this->steered());
 200 }
 201
 202 void RRTS::join_steered(RRTNode *f)
 203 {
 204         while (this->steered().size() > 0) {
 205                 this->store_node(this->steered().front());
 206                 RRTNode *t = &this->nodes().back();
 207                 t->p(f);
 208                 t->c(this->cost_build(*f, *t));
 209                 this->steered().erase(this->steered().begin());
 210                 f = t;
 211         }
 212 }
 213
 214 bool RRTS::goal_found(RRTNode &f)
 215 {
 216         bool found = false;
 217         for (auto &g: this->goals()) {
 218                 double cost = this->cost_build(f, g);
 219                 double edist = sqrt(
 220                         pow(f.x() - g.x(), 2)
 221                         + pow(f.y() - g.y(), 2)
 222                 );
 223                 double adist = std::abs(f.h() - g.h());
 224                 if (edist < 0.05 && adist < M_PI / 32) {
 225                         found = true;
 226                         if (g.p() == nullptr || cc(f) + cost < cc(g)) {
 227                                 g.p(&f);
 228                                 g.c(cost);
 229                         }
 230                 }
 231         }
 232         return found;
 233 }
 234
 235 // RRT* procedures
 236 bool RRTS::connect()
 237 {
 238         RRTNode *t = &this->steered().front();
 239         RRTNode *f = this->nn(this->samples().back());
 240         double cost = this->cost_search(*f, *t);
 241         for (auto n: this->nv(*t)) {
 242                 if (
 243                         !std::get<0>(this->collide_two_nodes(*n, *t))
 244                         && this->cost_search(*n, *t) < cost
 245                 ) {
 246                         f = n;
 247                         cost = this->cost_search(*n, *t);
 248                 }
 249         }
 250         this->store_node(this->steered().front());
 251         t = &this->nodes().back();
 252         t->p(f);
 253         t->c(this->cost_build(*f, *t));
 254         t->set_t(RRTNodeType::connected);
 255         return true;
 256 }
 257
 258 void RRTS::rewire()
 259 {
 260         RRTNode *f = &this->nodes().back();
 261         for (auto n: this->nv(*f)) {
 262                 if (
 263                         !std::get<0>(this->collide_two_nodes(*f, *n))
 264                         && cc(*f) + this->cost_search(*f, *n) < cc(*n)
 265                 ) {
 266                         n->p(f);
 267                         n->c(this->cost_build(*f, *n));
 268                 }
 269         }
 270 }
 271
 272 // API
 273 void RRTS::init()
 274 {
 275 }
 276
 277 void RRTS::deinit()
 278 {
 279         this->nodes().clear();
 280         this->samples().clear();
 281         this->steered().clear();
 282         this->store_node(RRTNode()); // root
 283         this->icnt_ = 0;
 284         this->scnt_ = 0;
 285         this->pcnt_ = 0;
 286         this->gf_ = false;
 287 }
 288
 289 std::vector<RRTNode *> RRTS::path()
 290 {
 291         std::vector<RRTNode *> path;
 292         if (this->goals().size() == 0)
 293                 return path;
 294         RRTNode *goal = &this->goals().front();
 295         for (auto &n: this->goals()) {
 296                 if (
 297                         n.p() != nullptr
 298                         && (n.c() < goal->c() || goal->p() == nullptr)
 299                 ) {
 300                         goal = &n;
 301                 }
 302         }
 303         if (goal->p() == nullptr)
 304                 return path;
 305         while (goal != nullptr) {
 306                 path.push_back(goal);
 307                 goal = goal->p();
 308         }
 309         std::reverse(path.begin(), path.end());
 310         return path;
 311 }
 312
 313 bool RRTS::next()
 314 {
 315         if (this->icnt_ == 0)
 316                 this->tstart_ = std::chrono::high_resolution_clock::now();
 317         bool next = true;
 318         if (this->should_stop())
 319                 return false;
 320         this->sample();
 321         this->steer(
 322                 *this->nn(this->samples().back()),
 323                 this->samples().back()
 324         );
 325         if (std::get<0>(this->collide_steered_from(
 326                 *this->nn(this->samples().back())
 327         )))
 328                 return next;
 329         if (!this->connect())
 330                 return next;
 331         this->rewire();
 332         unsigned scnt = this->steered().size();
 333         this->steered().erase(this->steered().begin());
 334         this->join_steered(&this->nodes().back());
 335         RRTNode *just_added = &this->nodes().back();
 336         while (scnt > 0) {
 337                 scnt--;
 338                 for (auto &g: this->goals()) {
 339                         this->steer(*just_added, g);
 340                         if (std::get<0>(this->collide_steered_from(
 341                                 *just_added
 342                         )))
 343                                 continue;
 344                         this->join_steered(just_added);
 345                 }
 346                 this->gf(this->goal_found(this->nodes().back()));
 347                 just_added = just_added->p();
 348         }
 349         return next;
 350 }
 351
 352 void RRTS::set_sample(
 353         double mx, double dx,
 354         double my, double dy,
 355         double mh, double dh
 356 )
 357 {
 358         this->ndx_ = std::normal_distribution<double>(mx, dx);
 359         this->ndy_ = std::normal_distribution<double>(my, dy);
 360         this->ndh_ = std::normal_distribution<double>(mh, dh);
 361 }
 362
 363 Json::Value RRTS::json()
 364 {
 365         Json::Value jvo;
 366         {
 367                 jvo["time"] = this->scnt();
 368         }
 369         {
 370                 jvo["iterations"] = this->icnt();
 371         }
 372         {
 373                 jvo["init"][0] = this->nodes().front().x();
 374                 jvo["init"][1] = this->nodes().front().y();
 375                 jvo["init"][2] = this->nodes().front().h();
 376         }
 377         {
 378                 if (this->path().size() > 0) {
 379                         jvo["cost"] = cc(*this->path().back());
 380                         jvo["goal"][0] = this->path().back()->x();
 381                         jvo["goal"][1] = this->path().back()->y();
 382                         jvo["goal"][2] = this->path().back()->h();
 383                 }
 384         }
 385         {
 386                 unsigned int cu = 0;
 387                 unsigned int co = 0;
 388                 unsigned int pcnt = 0;
 389                 for (auto n: this->path()) {
 390                         jvo["path"][pcnt][0] = n->x();
 391                         jvo["path"][pcnt][1] = n->y();
 392                         jvo["path"][pcnt][2] = n->h();
 393                         if (n->t(RRTNodeType::cusp))
 394                                 cu++;
 395                         if (n->t(RRTNodeType::connected))
 396                                 co++;
 397                         pcnt++;
 398                 }
 399                 jvo["cusps-in-path"] = cu;
 400                 jvo["connecteds-in-path"] = co;
 401         }
 402         {
 403                 unsigned int gcnt = 0;
 404                 for (auto g: this->goals()) {
 405                         jvo["goals"][gcnt][0] = g.x();
 406                         jvo["goals"][gcnt][1] = g.y();
 407                         jvo["goals"][gcnt][2] = g.h();
 408                         gcnt++;
 409                 }
 410         }
 411         {
 412                 unsigned int ocnt = 0;
 413                 for (auto o: this->obstacles()) {
 414                         unsigned int ccnt = 0;
 415                         for (auto c: o.poly()) {
 416                                 jvo["obst"][ocnt][ccnt][0] = std::get<0>(c);
 417                                 jvo["obst"][ocnt][ccnt][1] = std::get<1>(c);
 418                                 ccnt++;
 419                         }
 420                         ocnt++;
 421                 }
 422         }
 423         {
 424                 jvo["nodes"] = (unsigned int) this->nodes().size();
 425         }
 426         //{
 427         //        unsigned int ncnt = 0;
 428         //        for (auto n: this->nodes()) {
 429         //                jvo["nodes_x"][ncnt] = n.x();
 430         //                jvo["nodes_y"][ncnt] = n.y();
 431         //                //jvo["nodes_h"][ncnt] = n.h();
 432         //                ncnt++;
 433         //        }
 434         //}
 435         return jvo;
 436 }
 437
 438 void RRTS::json(Json::Value jvi)
 439 {
 440         assert(jvi["init"] != Json::nullValue);
 441         assert(jvi["goal"] != Json::nullValue);
 442         assert(jvi["goals"] != Json::nullValue);
 443         assert(jvi["obst"] != Json::nullValue);
 444
 445         this->nodes().front().x(jvi["init"][0].asDouble());
 446         this->nodes().front().y(jvi["init"][1].asDouble());
 447         this->nodes().front().h(jvi["init"][2].asDouble());
 448         {
 449                 RRTNode tmp_node;
 450                 tmp_node.x(jvi["goal"][0].asDouble());
 451                 tmp_node.y(jvi["goal"][1].asDouble());
 452                 tmp_node.h(jvi["goal"][2].asDouble());
 453                 this->goals().push_back(tmp_node);
 454                 for (auto g: jvi["goals"]) {
 455                         tmp_node.x(g[0].asDouble());
 456                         tmp_node.y(g[1].asDouble());
 457                         tmp_node.h(g[2].asDouble());
 458                         this->goals().push_back(tmp_node);
 459                 }
 460         }
 461         {
 462                 Obstacle tmp_obstacle;
 463                 for (auto o: jvi["obst"]) {
 464                         tmp_obstacle.poly().clear();
 465                         for (auto c: o) {
 466                                 double tmp_x = c[0].asDouble();
 467                                 double tmp_y = c[1].asDouble();
 468                                 auto tmp_tuple = std::make_tuple(tmp_x, tmp_y);
 469                                 tmp_obstacle.poly().push_back(tmp_tuple);
 470                         }
 471                         this->obstacles().push_back(tmp_obstacle);
 472                 }
 473         }
 474         {
 475                 double edist_init_goal = sqrt(
 476                         pow(
 477                                 this->nodes().front().x()
 478                                 - this->goals().front().x(),
 479                                 2
 480                         )
 481                         + pow(
 482                                 this->nodes().front().y()
 483                                 - this->goals().front().y(),
 484                                 2
 485                         )
 486                 );
 487                 this->set_sample(
 488                         this->nodes().front().x(), edist_init_goal,
 489                         this->nodes().front().y(), edist_init_goal,
 490                         0, 2 * M_PI
 491                 );
 492         }
 493 }
 494
 495 RRTS::RRTS()
 496         : gen_(std::random_device{}())
 497 {
 498         this->goals().reserve(100);
 499         this->nodes().reserve(4000000);
 500         this->samples().reserve(1000);
 501         this->steered().reserve(20000);
 502         this->store_node(RRTNode()); // root
 503 }
 504
 505 double cc(RRTNode &t)
 506 {
 507         RRTNode *n = &t;
 508         double cost = 0;
 509         while (n != nullptr) {
 510                 cost += n->c();
 511                 n = n->p();
 512         }
 513         return cost;
 514 }