servoSimuPoint2DCamVelocity3.cpp

Servo a point:

• eye-in-hand control law,
• velocity computed in the camera frame,
• no display.

wrt. servoSimuPoint2DCamVelocity1.cpp only the type of control law is modified. This illustrates the need for Jacobian update and Twist transformation matrix initialization, only the X coordinate is selected.

Only the X coordinate is selected (test the selection process).

/****************************************************************************
 *
 * ViSP, open source Visual Servoing Platform software.
 * Copyright (C) 2005 - 2023 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 as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 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 https://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:
 * Simulation of a 2D visual servoing on a point.
 *
*****************************************************************************/
 
#include <stdio.h>
#include <stdlib.h>
 
#include <visp3/core/vpConfig.h>
#include <visp3/core/vpHomogeneousMatrix.h>
#include <visp3/core/vpMath.h>
#include <visp3/io/vpParseArgv.h>
#include <visp3/robot/vpSimulatorCamera.h>
#include <visp3/visual_features/vpFeatureBuilder.h>
#include <visp3/visual_features/vpFeaturePoint.h>
#include <visp3/vs/vpServo.h>
 
// List of allowed command line options
#define GETOPTARGS "h"
 
#ifdef ENABLE_VISP_NAMESPACE
using namespace VISP_NAMESPACE_NAME;
#endif
 
void usage(const char *name, const char *badparam);
bool getOptions(int argc, const char **argv);
 
void usage(const char *name, const char *badparam)
{
  fprintf(stdout, "\n\
Simulation of a 2D visual servoing on a point:\n\
- eye-in-hand control law,\n\
- articular velocity are computed,\n\
- without display,\n\
- only the X coordinate of the point is selected.\n\
          \n\
SYNOPSIS\n\
  %s [-h]\n",
          name);
 
  fprintf(stdout, "\n\
OPTIONS:                                               Default\n\
                  \n\
  -h\n\
       Print the help.\n");
 
  if (badparam)
    fprintf(stdout, "\nERROR: Bad parameter [%s]\n", badparam);
}
 
bool getOptions(int argc, const char **argv)
{
  const char *optarg_;
  int c;
  while ((c = vpParseArgv::parse(argc, argv, GETOPTARGS, &optarg_)) > 1) {
 
    switch (c) {
    case 'h':
      usage(argv[0], nullptr);
      return false;
 
    default:
      usage(argv[0], optarg_);
      return false;
    }
  }
 
  if ((c == 1) || (c == -1)) {
    // standalone param or error
    usage(argv[0], nullptr);
    std::cerr << "ERROR: " << std::endl;
    std::cerr << "  Bad argument " << optarg_ << std::endl << std::endl;
    return false;
  }
 
  return true;
}
 
int main(int argc, const char **argv)
{
#if (defined(VISP_HAVE_LAPACK) || defined(VISP_HAVE_EIGEN3) || defined(VISP_HAVE_OPENCV))
  try {
    // Read the command line options
    if (getOptions(argc, argv) == false) {
      return EXIT_FAILURE;
    }
 
    vpServo task;
    vpSimulatorCamera robot;
 
    std::cout << std::endl;
    std::cout << "-------------------------------------------------------" << std::endl;
    std::cout << " Test program for vpServo " << std::endl;
    std::cout << " Eye-in-hand task control,  articular velocity are computed" << std::endl;
    std::cout << " Simulation " << std::endl;
    std::cout << " task : servo a point " << std::endl;
    std::cout << "-------------------------------------------------------" << std::endl;
    std::cout << std::endl;
 
    // sets the initial camera location
    vpHomogeneousMatrix cMo;
    cMo[0][3] = 0.1;
    cMo[1][3] = 0.2;
    cMo[2][3] = 2;
    // Compute the position of the object in the world frame
    vpHomogeneousMatrix wMc, wMo;
    robot.getPosition(wMc);
    wMo = wMc * cMo;
 
    // sets the point coordinates in the world frame
    vpPoint point(0, 0, 0);
 
    // computes the point coordinates in the camera frame and its 2D
    // coordinates
    point.track(cMo);
 
    // sets the current position of the visual feature
    vpFeaturePoint p;
    vpFeatureBuilder::create(p, point); // retrieve x,y and Z of the vpPoint structure
 
    // sets the desired position of the visual feature
    vpFeaturePoint pd;
    pd.buildFrom(0, 0, 1); // buildFrom(x,y,Z) ;
 
    // define the task
    // - we want an eye-in-hand control law
    // - articular velocity are computed
    task.setServo(vpServo::EYEINHAND_L_cVe_eJe);
 
    // Set the position of the end-effector frame in the camera frame as identity
    vpHomogeneousMatrix cMe;
    vpVelocityTwistMatrix cVe(cMe);
    task.set_cVe(cVe);
 
    // Set the Jacobian (expressed in the end-effector frame)
    vpMatrix eJe;
    robot.get_eJe(eJe);
    task.set_eJe(eJe);
 
    // we want to see a point on a point
    task.addFeature(p, pd, vpFeaturePoint::selectX());
 
    // set the gain
    task.setLambda(1);
 
    // Display task information
    task.print();
 
    unsigned int iter = 0;
    // loop
    while (iter++ < 100) {
      std::cout << "---------------------------------------------" << iter << std::endl;
      vpColVector v;
 
      // Set the Jacobian (expressed in the end-effector frame)
      // since q is modified eJe is modified
      robot.get_eJe(eJe);
      task.set_eJe(eJe);
 
      // get the robot position
      robot.getPosition(wMc);
      // Compute the position of the object frame in the camera frame
      cMo = wMc.inverse() * wMo;
 
      // new point position
      point.track(cMo);
      vpFeatureBuilder::create(p, point); // retrieve x,y and Z of the vpPoint structure
 
      // compute the control law
      v = task.computeControlLaw();
 
      // send the camera velocity to the controller
      robot.setVelocity(vpRobot::CAMERA_FRAME, v);
 
      std::cout << "|| s - s* || = " << (task.getError()).sumSquare() << std::endl;
    }
 
    // Display task information
    task.print();
    return EXIT_SUCCESS;
  }
  catch (const vpException &e) {
    std::cout << "Catch a ViSP exception: " << e << std::endl;
    return EXIT_FAILURE;
  }
#else
  (void)argc;
  (void)argv;
  std::cout << "Cannot run this example: install Lapack, Eigen3 or OpenCV" << std::endl;
  return EXIT_SUCCESS;
#endif
}