Visual Servoing Platform  version 3.2.0 under development (2018-12-12)
servoSimuSphere.cpp

Demonstration of the wireframe simulator with a simple visual servoing.

/****************************************************************************
*
* This file is part of the ViSP software.
* Copyright (C) 2005 - 2017 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 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:
* Demonstration of the wireframe simulator with a simple visual servoing
*
* Authors:
* Nicolas Melchior
*
*****************************************************************************/
#include <cmath> // std::fabs
#include <limits> // numeric_limits
#include <stdlib.h>
#include <visp3/core/vpCameraParameters.h>
#include <visp3/core/vpHomogeneousMatrix.h>
#include <visp3/core/vpImage.h>
#include <visp3/core/vpIoTools.h>
#include <visp3/core/vpMath.h>
#include <visp3/core/vpSphere.h>
#include <visp3/core/vpTime.h>
#include <visp3/core/vpVelocityTwistMatrix.h>
#include <visp3/gui/vpDisplayD3D.h>
#include <visp3/gui/vpDisplayGDI.h>
#include <visp3/gui/vpDisplayGTK.h>
#include <visp3/gui/vpDisplayOpenCV.h>
#include <visp3/gui/vpDisplayX.h>
#include <visp3/io/vpImageIo.h>
#include <visp3/io/vpParseArgv.h>
#include <visp3/robot/vpSimulatorCamera.h>
#include <visp3/robot/vpWireFrameSimulator.h>
#include <visp3/visual_features/vpFeatureBuilder.h>
#include <visp3/visual_features/vpGenericFeature.h>
#include <visp3/vs/vpServo.h>
#define GETOPTARGS "dh"
#ifdef VISP_HAVE_DISPLAY
void usage(const char *name, const char *badparam);
bool getOptions(int argc, const char **argv, bool &display);
void computeVisualFeatures(const vpSphere &sphere, vpGenericFeature &s);
void computeInteractionMatrix(const vpGenericFeature &s, const vpSphere &sphere, vpMatrix &L);
void usage(const char *name, const char *badparam)
{
fprintf(stdout, "\n\
Demonstration of the wireframe simulator with a simple visual servoing.\n\
\n\
The visual servoing consists in bringing the camera at a desired position from the object.\n\
\n\
The visual features used to compute the pose of the camera and thus the control law are special moments computed with the sphere's parameters.\n\
\n\
SYNOPSIS\n\
%s [-d] [-h]\n", name);
fprintf(stdout, "\n\
OPTIONS: Default\n\
-d \n\
Turn off the display.\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, bool &display)
{
const char *optarg_;
int c;
while ((c = vpParseArgv::parse(argc, argv, GETOPTARGS, &optarg_)) > 1) {
switch (c) {
case 'd':
display = false;
break;
case 'h':
usage(argv[0], NULL);
return false;
break;
default:
usage(argv[0], optarg_);
return false;
break;
}
}
if ((c == 1) || (c == -1)) {
// standalone param or error
usage(argv[0], NULL);
std::cerr << "ERROR: " << std::endl;
std::cerr << " Bad argument " << optarg_ << std::endl << std::endl;
return false;
}
return true;
}
/*
Computes the virtual visual features corresponding to the sphere and stores
it in the generic feature.
The visual feature vector is computed thanks to the following formula : s =
{sx, sy, sz} sx = gx*h2/(sqrt(h2+1) sx = gy*h2/(sqrt(h2+1) sz = sqrt(h2+1)
with gx and gy the center of gravity of the ellipse,
with h2 = (gx²+gy²)/(4*n20*gy²+4*n02*gx²-8n11gxgy)
with n20,n02,n11 the second order moments of the sphere
*/
void computeVisualFeatures(const vpSphere &sphere, vpGenericFeature &s)
{
double gx = sphere.get_x();
double gy = sphere.get_y();
double m02 = sphere.get_mu02();
double m20 = sphere.get_mu20();
double m11 = sphere.get_mu11();
double h2;
// if (gx != 0 || gy != 0)
if (std::fabs(gx) > std::numeric_limits<double>::epsilon() || std::fabs(gy) > std::numeric_limits<double>::epsilon())
h2 = (vpMath::sqr(gx) + vpMath::sqr(gy)) /
(4 * m20 * vpMath::sqr(gy) + 4 * m02 * vpMath::sqr(gx) - 8 * m11 * gx * gy);
else
h2 = 1 / (4 * m20);
double sx = gx * h2 / (sqrt(h2 + 1));
double sy = gy * h2 / (sqrt(h2 + 1));
double sz = sqrt(h2 + 1); //(h2-(vpMath::sqr(sx)+vpMath::sqr(sy)-1))/(2*sqrt(h2));
s.set_s(sx, sy, sz);
}
/*
Computes the interaction matrix such as L = [-1/R*I3 [s]x]
with R the radius of the sphere
with I3 the 3x3 identity matrix
with [s]x the skew matrix related to s
*/
void computeInteractionMatrix(const vpGenericFeature &s, const vpSphere &sphere, vpMatrix &L)
{
L = 0;
L[0][0] = -1 / sphere.getR();
L[1][1] = -1 / sphere.getR();
L[2][2] = -1 / sphere.getR();
double s0, s1, s2;
s.get_s(s0, s1, s2);
vpTranslationVector c(s0, s1, s2);
sk = c.skew();
for (unsigned int i = 0; i < 3; i++)
for (unsigned int j = 0; j < 3; j++)
L[i][j + 3] = sk[i][j];
}
int main(int argc, const char **argv)
{
try {
bool opt_display = true;
// Read the command line options
if (getOptions(argc, argv, opt_display) == false) {
exit(-1);
}
vpImage<vpRGBa> Iint(480, 640, 255);
vpImage<vpRGBa> Iext1(480, 640, 255);
vpImage<vpRGBa> Iext2(480, 640, 255);
#if defined VISP_HAVE_X11
vpDisplayX display[3];
#elif defined VISP_HAVE_OPENCV
vpDisplayOpenCV display[3];
#elif defined VISP_HAVE_GDI
vpDisplayGDI display[3];
#elif defined VISP_HAVE_D3D9
vpDisplayD3D display[3];
#elif defined VISP_HAVE_GTK
vpDisplayGTK display[3];
#endif
if (opt_display) {
// Display size is automatically defined by the image (I) size
display[0].init(Iint, 100, 100, "The internal view");
display[1].init(Iext1, 100, 100, "The first external view");
display[2].init(Iext2, 100, 100, "The second external view");
}
vpServo task;
float sampling_time = 0.040f; // Sampling period in second
robot.setSamplingTime(sampling_time);
// Since the task gain lambda is very high, we need to increase default
// max velocities
// Set initial position of the object in the camera frame
vpHomogeneousMatrix cMo(0, 0.1, 2.0, vpMath::rad(35), vpMath::rad(25), 0);
// Set desired position of the object in the camera frame
vpHomogeneousMatrix cdMo(0.0, 0.0, 0.8, vpMath::rad(0), vpMath::rad(0), vpMath::rad(0));
// Set initial position of the object in the world frame
vpHomogeneousMatrix wMo(0.0, 0.0, 0, 0, 0, 0);
// Position of the camera in the world frame
wMc = wMo * cMo.inverse();
robot.setPosition(wMc);
// The sphere
vpSphere sphere(0, 0, 0, 0.15);
// Projection of the sphere
sphere.track(cMo);
// Set the current visual feature
computeVisualFeatures(sphere, s);
// Projection of the points
sphere.track(cdMo);
computeVisualFeatures(sphere, sd);
vpMatrix L(3, 6);
computeInteractionMatrix(sd, sphere, L);
sd.setInteractionMatrix(L);
task.set_cVe(cVe);
vpMatrix eJe;
robot.get_eJe(eJe);
task.set_eJe(eJe);
task.addFeature(s, sd);
task.setLambda(7);
// Set the scene
// Initialize simulator frames
sim.set_fMo(wMo); // Position of the object in the world reference frame
sim.setCameraPositionRelObj(cMo); // initial position of the camera
sim.setDesiredCameraPosition(cdMo); // desired position of the camera
// Set the External camera position
vpHomogeneousMatrix camMf(0.0, 0, 3.5, vpMath::rad(0), vpMath::rad(30), 0);
// Computes the position of a camera which is fixed in the object frame
vpHomogeneousMatrix camoMf(0, 0.0, 2.5, 0, vpMath::rad(140), 0);
camoMf = camoMf * (sim.get_fMo().inverse());
// Set the parameters of the cameras (internal and external)
vpCameraParameters camera(1000, 1000, 320, 240);
int stop = 10;
if (opt_display) {
stop = 1000;
// Get the internal and external views
sim.getInternalImage(Iint);
sim.getExternalImage(Iext1);
sim.getExternalImage(Iext2, camoMf);
// Display the object frame (current and desired position)
vpDisplay::displayFrame(Iint, cMo, camera, 0.2, vpColor::none);
vpDisplay::displayFrame(Iint, cdMo, camera, 0.2, vpColor::none);
// Display the object frame the world reference frame and the camera
// frame
vpDisplay::displayFrame(Iext1, camMf * sim.get_fMo() * cMo.inverse(), camera, 0.2, vpColor::none);
vpDisplay::displayFrame(Iext1, camMf * sim.get_fMo(), camera, 0.2, vpColor::none);
vpDisplay::displayFrame(Iext1, camMf, camera, 0.2, vpColor::none);
// Display the world reference frame and the object frame
vpDisplay::displayFrame(Iext2, camoMf, camera, 0.2, vpColor::none);
vpDisplay::displayFrame(Iext2, camoMf * sim.get_fMo(), camera, 0.05, vpColor::none);
std::cout << "Click on a display" << std::endl;
while (!vpDisplay::getClick(Iint, false) && !vpDisplay::getClick(Iext1, false) &&
!vpDisplay::getClick(Iext2, false)) {
};
}
// Print the task
task.print();
int iter = 0;
while (iter++ < stop) {
if (opt_display) {
}
double t = vpTime::measureTimeMs();
robot.get_eJe(eJe);
task.set_eJe(eJe);
wMc = robot.getPosition();
cMo = wMc.inverse() * wMo;
sphere.track(cMo);
// Set the current visual feature
computeVisualFeatures(sphere, s);
v = task.computeControlLaw();
// Compute the position of the external view which is fixed in the
// object frame
camoMf.buildFrom(0, 0.0, 2.5, 0, vpMath::rad(150), 0);
camoMf = camoMf * (sim.get_fMo().inverse());
if (opt_display) {
// Get the internal and external views
sim.getInternalImage(Iint);
sim.getExternalImage(Iext1);
sim.getExternalImage(Iext2, camoMf);
// Display the object frame (current and desired position)
vpDisplay::displayFrame(Iint, cMo, camera, 0.2, vpColor::none);
vpDisplay::displayFrame(Iint, cdMo, camera, 0.2, vpColor::none);
// Display the camera frame, the object frame the world reference
// frame
vpDisplay::displayFrame(Iext1, sim.getExternalCameraPosition() * sim.get_fMo() * cMo.inverse(), camera, 0.2,
// Display the world reference frame and the object frame
vpDisplay::displayFrame(Iext2, camoMf, camera, 0.2, vpColor::none);
vpDisplay::displayFrame(Iext2, camoMf * sim.get_fMo(), camera, 0.05, vpColor::none);
}
vpTime::wait(t, sampling_time * 1000); // Wait 40 ms
std::cout << "|| s - s* || = " << (task.getError()).sumSquare() << std::endl;
}
task.print();
task.kill();
return EXIT_SUCCESS;
} catch (const vpException &e) {
std::cout << "Catch an exception: " << e << std::endl;
return EXIT_FAILURE;
}
}
#else
int main()
{
std::cout << "You do not have X11, or GDI (Graphical Device Interface), or GTK functionalities to display images..." << std::endl;
std::cout << "Tip if you are on a unix-like system:" << std::endl;
std::cout << "- Install X11, configure again ViSP using cmake and build again this example" << std::endl;
std::cout << "Tip if you are on a windows-like system:" << std::endl;
std::cout << "- Install GDI, configure again ViSP using cmake and build again this example" << std::endl;
return EXIT_SUCCESS;
}
#endif