servoAfma6Points2DCamVelocityEyeToHand.cpp

Example of a eye-to-hand control law. We control here a real robot, the Afma6 robot (cartesian robot, with 6 degrees of freedom). The robot is controlled in the camera frame.

/****************************************************************************
 *
 * This file is part of the ViSP software.
 * Copyright (C) 2005 - 2015 by Inria. All rights reserved.
 *
 * This software is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * ("GPL") version 2 as published by the Free Software Foundation.
 * See the file LICENSE.txt at the root directory of this source
 * distribution for additional information about the GNU GPL.
 *
 * For using ViSP with software that can not be combined with the GNU
 * GPL, please contact Inria about acquiring a ViSP Professional
 * Edition License.
 *
 * See http://visp.inria.fr for more information.
 *
 * This software was developed at:
 * Inria Rennes - Bretagne Atlantique
 * Campus Universitaire de Beaulieu
 * 35042 Rennes Cedex
 * France
 *
 * If you have questions regarding the use of this file, please contact
 * Inria at visp@inria.fr
 *
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Description:
 *   tests the control law
 *   eye-to-hand control
 *   velocity computed in the camera frame
 *
 * Authors:
 * Eric Marchand
 *
 *****************************************************************************/
#include <visp3/core/vpConfig.h>
#include <visp3/core/vpDebug.h> // Debug trace
#include <stdlib.h>
#include <cmath>    // std::fabs
#include <limits>   // numeric_limits
#include <list>
#if (defined (VISP_HAVE_AFMA6) && defined (VISP_HAVE_DC1394))

#define SAVE 0

#include <visp3/sensor/vp1394TwoGrabber.h>
#include <visp3/core/vpImage.h>
#include <visp3/core/vpImagePoint.h>
#include <visp3/core/vpMath.h>
#include <visp3/core/vpHomogeneousMatrix.h>
#include <visp3/visual_features/vpFeaturePoint.h>
#include <visp3/core/vpPoint.h>
#include <visp3/vs/vpServo.h>
#include <visp3/visual_features/vpFeatureBuilder.h>
#include <visp3/robot/vpRobotAfma6.h>
#include <visp3/core/vpException.h>
#include <visp3/vs/vpServoDisplay.h>
#include <visp3/blob/vpDot.h>
#include <visp3/vision/vpPose.h>
#include <visp3/io/vpImageIo.h>
#include <visp3/core/vpDisplay.h>
#include <visp3/gui/vpDisplayX.h>
#include <visp3/gui/vpDisplayOpenCV.h>
#include <visp3/gui/vpDisplayGTK.h>

#define L 0.006
#define D 0

int main()
{
  try
  {
    vpServo task ;

    vpCameraParameters cam ;
    vpImage<unsigned char> I ;
    int i ;

    vp1394TwoGrabber g;
    g.setVideoMode(vp1394TwoGrabber::vpVIDEO_MODE_640x480_MONO8);
    g.setFramerate(vp1394TwoGrabber::vpFRAMERATE_60);
    g.open(I) ;

    g.acquire(I) ;

#ifdef VISP_HAVE_X11
    vpDisplayX display(I,100,100,"Current image") ;
#elif defined(VISP_HAVE_OPENCV)
    vpDisplayOpenCV display(I,100,100,"Current image") ;
#elif defined(VISP_HAVE_GTK)
    vpDisplayGTK display(I,100,100,"Current image") ;
#endif

    vpDisplay::display(I) ;
    vpDisplay::flush(I) ;

    std::cout << std::endl ;
    std::cout << "-------------------------------------------------------" << std::endl ;
    std::cout << " Test program for vpServo "  <<std::endl ;
    std::cout << " Eye-to-hand task control" << std::endl ;
    std::cout << " Simulation " << std::endl ;
    std::cout << " task : servo a point " << std::endl ;
    std::cout << "-------------------------------------------------------" << std::endl ;
    std::cout << std::endl ;

    int nbPoint =7 ;

    vpDot dot[nbPoint] ;
    vpImagePoint cog;

    for (i=0 ; i < nbPoint ; i++)
    {
      dot[i].initTracking(I) ;
      dot[i].setGraphics(true) ;
      dot[i].track(I) ;
      vpDisplay::flush(I) ;
      dot[i].setGraphics(false) ;
    }

    // Compute the pose 3D model
    vpPoint point[nbPoint] ;
    point[0].setWorldCoordinates(-2*L,D, -3*L) ;
    point[1].setWorldCoordinates(0,D, -3*L) ;
    point[2].setWorldCoordinates(2*L,D, -3*L) ;

    point[3].setWorldCoordinates(-L,D,-L) ;
    point[4].setWorldCoordinates(L,D, -L) ;
    point[5].setWorldCoordinates(L,D, L) ;
    point[6].setWorldCoordinates(-L,D, L) ;

    vpRobotAfma6 robot ;
    // Update camera parameters
    robot.getCameraParameters (cam, I);

    vpHomogeneousMatrix cMo, cdMo ;
    vpPose pose ;
    pose.clearPoint() ;
    for (i=0 ; i < nbPoint ; i++)
    {
      cog = dot[i].getCog();
      double x=0, y=0;
      vpPixelMeterConversion::convertPoint(cam, cog, x, y)  ;
      point[i].set_x(x) ;
      point[i].set_y(y) ;
      pose.addPoint(point[i]) ;
    }

    // compute the initial pose using Dementhon method followed by a non linear
    // minimisation method
    pose.computePose(vpPose::DEMENTHON_LOWE, cMo) ;


    std::cout << cMo << std::endl  ;
    cMo.print() ;

    /*------------------------------------------------------------------
    --  Learning the desired position
    --  or reading the desired position
    ------------------------------------------------------------------
    */
    std::cout << " Learning 0/1 " <<std::endl ;
    char name[FILENAME_MAX] ;
    sprintf(name,"cdMo.dat") ;
    int learning ;
    std::cin >> learning ;
    if (learning ==1)
    {
      // save the object position
      vpTRACE("Save the location of the object in a file cdMo.dat") ;
      std::ofstream f(name) ;
      cMo.save(f) ;
      f.close() ;
      exit(1) ;
    }


    {
      vpTRACE("Loading desired location from cdMo.dat") ;
      std::ifstream f("cdMo.dat") ;
      cdMo.load(f) ;
      f.close() ;
    }

    vpFeaturePoint p[nbPoint], pd[nbPoint] ;

    // set the desired position of the point by forward projection using
    // the pose cdMo
    for (i=0 ; i < nbPoint ; i++)
    {
      vpColVector cP, p ;
      point[i].changeFrame(cdMo, cP) ;
      point[i].projection(cP, p) ;

      pd[i].set_x(p[0]) ;
      pd[i].set_y(p[1]) ;
    }



    //------------------------------------------------------------------

    vpTRACE("define the task") ;
    vpTRACE("\t we want an eye-in-hand control law") ;
    vpTRACE("\t robot is controlled in the camera frame") ;
    task.setServo(vpServo::EYETOHAND_L_cVe_eJe) ;
    task.setInteractionMatrixType(vpServo::CURRENT) ;


    for (i=0 ; i < nbPoint ; i++)
    {
      task.addFeature(p[i],pd[i]) ;
    }


    vpTRACE("Display task information " ) ;
    task.print() ;


    //------------------------------------------------------------------


    double convergence_threshold = 0.00; //025 ;
    vpDisplay::getClick(I) ;

    //-------------------------------------------------------------
    double error =1 ;
    unsigned int iter=0 ;
    vpTRACE("\t loop") ;
    robot.setRobotState(vpRobot::STATE_VELOCITY_CONTROL) ;
    vpColVector v ; // computed robot velocity


    // position of the object in the effector frame
    vpHomogeneousMatrix oMcamrobot ;
    oMcamrobot[0][3] = -0.05 ;

    vpImage<vpRGBa> Ic ;
    int it = 0 ;

    double lambda_av =0.1;
    double alpha = 1 ; //1 ;
    double beta =3 ; //3 ;

    std::cout << "alpha 0.7" << std::endl;
    std::cin >> alpha ;
    std::cout << "beta 5" << std::endl;
    std::cin >> beta ;
    std::list<vpImagePoint> Lcog ;
    vpImagePoint ip;
    while(error > convergence_threshold)
    {
      std::cout << "---------------------------------------------" << iter++ <<std::endl ;

      g.acquire(I) ;
      vpDisplay::display(I) ;
      ip.set_i( 265 );
      ip.set_j( 150 );
      vpDisplay::displayText(I, ip, "Eye-To-Hand Visual Servoing", vpColor::green) ;
      ip.set_i( 280 );
      ip.set_j( 150 );
      vpDisplay::displayText(I, ip, "IRISA-INRIA Rennes, Lagadic project", vpColor::green) ;
      try
        {
          for (i=0 ; i < nbPoint ; i++)
            {
              dot[i].track(I) ;
          Lcog.push_back( dot[i].getCog() );
            }
        }
      catch(...)
        {
          vpTRACE("Error detected while tracking visual features") ;
          robot.stopMotion() ;
          exit(1) ;
        }

      // compute the initial pose using  a non linear minimisation method
      pose.clearPoint() ;

      for (i=0 ; i < nbPoint ; i++)
        {
          double x=0, y=0;
          cog = dot[i].getCog();
          vpPixelMeterConversion::convertPoint(cam, cog, x, y)  ;
          point[i].set_x(x) ;
          point[i].set_y(y) ;

          vpColVector cP ;
          point[i].changeFrame(cdMo, cP) ;

          p[i].set_x(x) ;
          p[i].set_y(y) ;
          p[i].set_Z(cP[2]) ;

          pose.addPoint(point[i]) ;

          point[i].display(I,cMo,cam, vpColor::green) ;
          point[i].display(I,cdMo,cam, vpColor::blue) ;
        }
      pose.computePose(vpPose::LOWE, cMo) ;
      vpDisplay::flush(I) ;

      vpHomogeneousMatrix cMe, camrobotMe ;
      robot.get_cMe(camrobotMe) ;
      cMe = cMo *oMcamrobot * camrobotMe  ;


      task.set_cVe(cMe) ;

      vpMatrix eJe ;
      robot.get_eJe(eJe) ;
      task.set_eJe(eJe) ;


      // Compute the adaptative gain (speed up the convergence)
      double gain ;
      if (iter>2)
      {
        if (std::fabs(alpha) <= std::numeric_limits<double>::epsilon())
          gain = lambda_av ;
        else
        {
          gain = alpha * exp (-beta * ( task.getError() ).sumSquare() ) +  lambda_av;
        }
      }
      else gain = lambda_av ;
      if (SAVE==1)
        gain = gain/5 ;

      vpTRACE("%f %f %f %f  %f",alpha, beta, lambda_av, ( task.getError() ).sumSquare(),  gain) ;
      task.setLambda(gain) ;


      v = task.computeControlLaw() ;

      // display points trajectory
      for (std::list<vpImagePoint>::const_iterator it_cog = Lcog.begin(); it_cog != Lcog.end(); ++it_cog)
      {
        vpDisplay::displayPoint(I, *it_cog, vpColor::red) ;
      }
      vpServoDisplay::display(task,cam,I) ;
      robot.setVelocity(vpRobot::ARTICULAR_FRAME, v) ;

      error = ( task.getError() ).sumSquare() ;
      std::cout << "|| s - s* || = "<< error<<std::endl ;

      if (error>7)
        {
          vpTRACE("Error detected while tracking visual features") ;
          robot.stopMotion() ;
          exit(1) ;
        }

      // display the pose
      // pose.display(I,cMo,cam, 0.04, vpColor::red) ;
      // display the pose
      //   pose.display(I,cdMo,cam, 0.04, vpColor::blue) ;
      if ((SAVE==1) && (iter %3==0))
        {

          vpDisplay::getImage(I,Ic) ;
          sprintf(name,"/tmp/marchand/image.%04d.ppm",it++) ;
        vpImageIo::write(Ic,name) ;
        }
    }
    v = 0 ;
    robot.setVelocity(vpRobot::CAMERA_FRAME, v) ;
    vpDisplay::getClick(I) ;
    task.kill();
  }
  catch (...)
  {
    vpERROR_TRACE(" Test failed") ;
    return 0;
  }
}

#else
int
main()
{
  vpERROR_TRACE("You do not have an afma6 robot or a firewire framegrabber connected to your computer...");
}

#endif