avoidance_resolution.h

Go to the documentation of this file.

/*
 * Copyright (c) 2017, <copyright holder> <email>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *     * Neither the name of the <organization> nor the
 *     names of its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY <copyright holder> <email> ''AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL <copyright holder> <email> BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#ifndef AVOIDANCE_RESOLUTION_H
#define AVOIDANCE_RESOLUTION_H

#include <tuw_global_router/srr_utils.h>
#include <tuw_global_router/route_coordinator.h>
#include <tuw_global_router/collision_resolution.h>
#include <queue>

namespace multi_robot_router
{
class AvoidanceResolution : public CollisionResolution
{
  public:
    AvoidanceResolution(uint32_t _timeoverlap);
    AvoidanceResolution();

    void resetSession(const RouteCoordinatorWrapper *_route_querry, const PotentialCalculator *_pCalc, const uint32_t _robot_radius);
    std::vector<std::reference_wrapper<Vertex>> resolve(Vertex &_current, Vertex &_next, int32_t _collision);
    const std::vector<uint32_t> &getRobotCollisions() const;
    void saveCollision(const uint32_t _coll);

  private:
    struct queueElement
    {
        Vertex *current;
        Vertex *next;
        int32_t collision;
        float potential;
    };

    //Tracks back until a free vertex or the start vertex is found to avoid a robot
    void trackBack(Vertex &_current, Vertex &_next, const int32_t _collision, const float _freePotential);
    //Tries to avoid a robot on a free segment of a crossing, which is not part of the route
    void avoid(Vertex &_current, Vertex &_next, const int32_t _collision, const float _freePotential);
    //Expands to the next segment and back to the current one
    void moveSegment(Vertex &_current, Vertex &_next, const int32_t _collision, const float _freePotential);
    //Expands to the next segment and back to the current one
    bool expandSegment(const Vertex &cSeg, Vertex &_current, Vertex &_next, const int32_t _collision, const float _freePotential);
    //Avoids a robot by inserting a wait Vertex before start
    void avoidStart(Vertex &_current, Vertex &_next, const int32_t _collision, const float _freePotential);
    //Avoids a robot by inserting a wait Vertex after goal
    void avoidGoal(Vertex &_current, Vertex &_next, const int32_t _collision, const float _freePotential);
    //Saves robot collisions automatically extending the collision vertex
    void addCollision(const uint32_t robot);

    const RouteCoordinatorWrapper *route_querry_;
    const PotentialCalculator *pCalc_;
    uint32_t timeoverlap_;
    uint32_t robotDiameter_;
    //unique_ptr to keep references of Vertex (Heap), because the list is updated while runtime
    std::vector<std::vector<std::unique_ptr<Vertex>>> generatedSubgraphs_;
    std::vector<std::reference_wrapper<Vertex>> foundSolutions_;
    std::vector<uint32_t> encounteredCollisions_;
    uint32_t resolutionAttemp_ = 0;
    bool avoidStartSuccessorDone_ = false;
    bool avoidStartPredecessorDone_ = false;
    std::queue<queueElement> queue_;
};
} // namespace multi_robot_router
#endif // HEURISTIC_H