Example: nav_circ_robot_path_planning

This example shows the use of the basic 2D path planning algorithm implemented in the mrpt-nav class PlannerSimple2D.

See also: [index of motion planning algorithms]()

C++ example source code:

/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2024, Individual contributors, see AUTHORS file     |
   | See: https://www.mrpt.org/Authors - All rights reserved.               |
   | Released under BSD License. See: https://www.mrpt.org/License          |
   +------------------------------------------------------------------------+ */

#include <mrpt/gui/CDisplayWindow3D.h>
#include <mrpt/io/CFileGZInputStream.h>
#include <mrpt/maps/COccupancyGridMap2D.h>
#include <mrpt/nav/planners/PlannerSimple2D.h>
#include <mrpt/poses/CPose2D.h>
#include <mrpt/serialization/CArchive.h>
#include <mrpt/system/CTicTac.h>
#include <mrpt/system/filesystem.h>

#include <iostream>

using namespace mrpt;
using namespace mrpt::maps;
using namespace mrpt::nav;
using namespace mrpt::serialization;
using namespace mrpt::img;
using namespace mrpt::math;
using namespace mrpt::poses;
using namespace mrpt::io;
using namespace mrpt::system;
using namespace std;

#include <mrpt/examples_config.h>

string myGridMap(
    MRPT_EXAMPLES_BASE_DIRECTORY +
    string("../share/mrpt/datasets/2006-MalagaCampus.gridmap.gz"));

// ------------------------------------------------------
//              TestPathPlanning
// ------------------------------------------------------
void TestPathPlanning()
{
    // Load the gridmap:
    COccupancyGridMap2D gridmap;

    if (!mrpt::system::fileExists(myGridMap))
        THROW_EXCEPTION_FMT("Map file '%s' not found", myGridMap.c_str());

    printf("Loading gridmap...");
    {
        CFileGZInputStream f(myGridMap);
        auto arch = archiveFrom(f);
        arch >> gridmap;
    }
    printf(
        "Done! %f x %f m\n", gridmap.getXMax() - gridmap.getXMin(),
        gridmap.getYMax() - gridmap.getYMin());

    // Find path:
    PlannerSimple2D pathPlanning;
    pathPlanning.robotRadius = 0.30f;

    std::deque<TPoint2D> thePath;
    bool notFound;
    CTicTac tictac;

    CPose2D origin(20, -110, 0);
    CPose2D target(90, 40, 0);

    cout << "Origin: " << origin << endl;
    cout << "Target: " << target << endl;

    cout << "Searching path...";
    cout.flush();
    tictac.Tic();

    pathPlanning.computePath(gridmap, origin, target, thePath, notFound);

    double t = tictac.Tac();
    cout << "Done in " << t * 1000 << " ms" << endl;

    printf("Path found: %s\n", notFound ? "NO" : "YES");
    printf("Path has %u steps\n", (unsigned)thePath.size());

    // Save result:
    CImage img;
    gridmap.getAsImage(img, false, true);  // Force a RGB image

    // Draw the path:
    // ---------------------
    int R = round(pathPlanning.robotRadius / gridmap.getResolution());

    for (std::deque<TPoint2D>::const_iterator it = thePath.begin();
         it != thePath.end(); ++it)
        img.drawCircle(
            gridmap.x2idx(it->x), gridmap.getSizeY() - 1 - gridmap.y2idx(it->y),
            R, TColor(0, 0, 255));

    img.drawMark(
        gridmap.x2idx(origin.x()),
        gridmap.getSizeY() - 1 - gridmap.y2idx(origin.y()),
        TColor(0x20, 0x20, 0x20), '+', 10);
    img.drawMark(
        gridmap.x2idx(target.x()),
        gridmap.getSizeY() - 1 - gridmap.y2idx(target.y()),
        TColor(0x50, 0x50, 0x50), 'x', 10);

    const std::string dest = "path_planning.png";
    cout << "Saving output to: " << dest << endl;
    img.saveToFile(dest);
    printf("Done\n");

#if MRPT_HAS_WXWIDGETS
    mrpt::gui::CDisplayWindow3D win("Computed path");
    win.setImageView(img);
    win.repaint();

    win.waitForKey();
#endif
}

int main(int argc, char** argv)
{
    try
    {
        TestPathPlanning();
        return 0;
    }
    catch (exception& e)
    {
        cout << "MRPT exception caught: " << e.what() << endl;
        return -1;
    }
    catch (...)
    {
        printf("Another exception!!");
        return -1;
    }
}