servoSimuThetaUCamVelocity.cpp

Simulation of a visual servoing using theta U visual features:

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

/*
 * ViSP, open source Visual Servoing Platform software.
 * Copyright (C) 2005 - 2025 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 visual servoing using theta U visual features.
 *   tests the control law
 *   eye-in-hand control
 *   velocity computed in the camera frame
 *   using theta U visual feature
 */

 
#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/vpFeatureThetaU.h>
#include <visp3/visual_features/vpFeatureTranslation.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 avisual servoing using theta U visual feature:\n\
- eye-in-hand control law,\n\
- velocity computed in the camera frame,\n\
- without display.\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, velocity computed in the camera frame" << std::endl;
    std::cout << " Simulation " << std::endl;
    std::cout << " task :  servo using theta U visual feature " << std::endl;
    std::cout << "-------------------------------------------------------" << std::endl;
    std::cout << std::endl;
 
    // sets the initial camera location
    vpPoseVector c_r_o(0.1, 0.2, 2, vpMath::rad(20), vpMath::rad(10), vpMath::rad(50));
 
    vpHomogeneousMatrix cMo(c_r_o);
    // Compute the position of the object in the world frame
    vpHomogeneousMatrix wMc, wMo;
    robot.getPosition(wMc);
    wMo = wMc * cMo;
 
    // sets the desired camera location
    vpPoseVector cd_r_o(0, 0, 1, vpMath::rad(0), vpMath::rad(0), vpMath::rad(0));
    vpHomogeneousMatrix cdMo(cd_r_o);
 
    // compute the rotation that the camera has to realize
    vpHomogeneousMatrix cdMc;
    cdMc = cdMo * cMo.inverse();
    vpFeatureThetaU tu(vpFeatureThetaU::cdRc);
    tu.buildFrom(cdMc);
 
    // define the task
    // - we want an eye-in-hand control law
    // - robot is controlled in the camera frame
    task.setServo(vpServo::EYEINHAND_CAMERA);
    task.setInteractionMatrixType(vpServo::DESIRED);
 
    task.addFeature(tu);
 
    // - set the gain
    task.setLambda(1);
 
    // Display task information
    task.print();
 
    unsigned int iter = 0;
    // loop
    while (iter++ < 200) {
      std::cout << "---------------------------------------------" << iter << std::endl;
      vpColVector v;
 
      // get the robot position
      robot.getPosition(wMc);
      // Compute the position of the object frame in the camera frame
      cMo = wMc.inverse() * wMo;
 
      // new rotation to achieve
      cdMc = cdMo * cMo.inverse();
      tu.buildFrom(cdMc);
 
      // 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
}