Visual Servoing Platform  version 3.6.1 under development (2024-04-16)

Visual servoing experiment on a circle with a visualization from the camera and from an external view using vpSimulator.

* 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 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
* This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
* Description:
* Simulation of a visual servoing with visualization.
#include <visp3/core/vpConfig.h>
#include <visp3/core/vpDebug.h>
#include <visp3/ar/vpSimulator.h>
#include <visp3/core/vpCameraParameters.h>
#include <visp3/core/vpCircle.h>
#include <visp3/core/vpHomogeneousMatrix.h>
#include <visp3/core/vpImage.h>
#include <visp3/core/vpIoTools.h>
#include <visp3/core/vpMath.h>
#include <visp3/core/vpTime.h>
#include <visp3/io/vpParseArgv.h>
#include <visp3/robot/vpSimulatorCamera.h>
#include <visp3/visual_features/vpFeatureBuilder.h>
#include <visp3/visual_features/vpFeatureEllipse.h>
#include <visp3/vs/vpServo.h>
#define GETOPTARGS "cdi:h"
#define SAVE 0
void usage(const char *name, const char *badparam, std::string ipath)
fprintf(stdout, "\n\
Simulation Servo Circle\n\
%s [-i <input image path>] [-d] [-h]\n",
fprintf(stdout, "\n\
OPTIONS: Default\n\
-i <input image path> %s\n\
Set image input path.\n\
From this path read \"iv/4points.iv\"\n\
cad model.\n\
Setting the VISP_INPUT_IMAGE_PATH environment\n\
variable produces the same behaviour than using\n\
this option.\n\
-d \n\
Disable the image display. This can be useful \n\
for automatic tests using crontab under Unix or \n\
using the task manager under Windows.\n\
Print the help.\n\n",
if (badparam)
fprintf(stdout, "\nERROR: Bad parameter [%s]\n", badparam);
bool getOptions(int argc, const char **argv, std::string &ipath, bool &display)
const char *optarg;
int c;
while ((c = vpParseArgv::parse(argc, argv, GETOPTARGS, &optarg)) > 1) {
switch (c) {
case 'i':
ipath = optarg;
case 'd':
display = false;
case 'h':
usage(argv[0], nullptr, ipath);
return false;
usage(argv[0], optarg, ipath);
return false;
if ((c == 1) || (c == -1)) {
// standalone param or error
usage(argv[0], nullptr, ipath);
std::cerr << "ERROR: " << std::endl;
std::cerr << " Bad argument " << optarg << std::endl << std::endl;
return false;
return true;
static void *mainLoop(void *_simu)
vpSimulator *simu = static_cast<vpSimulator *>(_simu);
vcMo[0] = 0.3;
vcMo[1] = 0.2;
vcMo[2] = 3;
vcMo[3] = 0;
vcMo[4] = vpMath::rad(45);
vcMo[5] = vpMath::rad(40);
vpHomogeneousMatrix wMo; // Set to identity
vpHomogeneousMatrix wMc; // Robot (=camera) location in the world frame
cMod[0][3] = 0;
cMod[1][3] = 0;
cMod[2][3] = 1;
int it = 0;
unsigned int pos = 2;
while (pos != 0) {
vpServo task;
float sampling_time = 0.040f; // Sampling period in second
// Sets the initial camera location
wMc = wMo * cMo.inverse();
if (pos == 1)
cMod[2][3] = 0.32;
// Sets the circle coordinates in the world frame
vpCircle circle;
circle.setWorldCoordinates(0, 0, 1, 0, 0, 0, 0.1);
// Sets the desired position of the visual feature
// Project : computes the circle coordinates in the camera frame and its
// 2D coordinates Sets the current position of the visual feature
// Define the task
// We want an eye-in-hand control law
// Robot is controlled in the camera frame
// We want to see a circle on a circle
std::cout << std::endl;
task.addFeature(p, pd);
// Set the gain
// Display task information
vpTime::wait(1000); // Sleep 1s
unsigned int iter = 0;
// Visual servoing loop
unsigned int itermax;
if (pos == 2)
itermax = 75;
itermax = 100;
while (iter++ < itermax) {
double t = vpTime::measureTimeMs();
if (iter == 1)
std::cout << "get the robot position" << std::endl;
wMc = robot.getPosition();
if (iter == 1)
std::cout << "new circle position" << std::endl;
// retrieve x,y and Z of the vpCircle structure
cMo = wMc.inverse() * wMo;
if (iter == 1)
std::cout << "compute the control law" << std::endl;
if (iter == 1) {
std::cout << "Task rank: " << task.getTaskRank() << std::endl;
std::cout << "send the camera velocity to the controller" << std::endl;
if (SAVE == 1) {
char name[FILENAME_MAX];
snprintf(name, FILENAME_MAX, "/tmp/image.%04d.external.png", it);
std::cout << "Save " << name << std::endl;
snprintf(name, FILENAME_MAX, "/tmp/image.%04u.internal.png", iter);
std::cout << "Save " << name << std::endl;
// std::cout << "\t\t || s - s* || "
// std::cout << ( task.getError() ).sumSquare() <<std::endl ; ;
vpTime::wait(t, sampling_time * 1000); // Wait 40 ms
void *a = nullptr;
return a;
int main(int argc, const char **argv)
try {
std::string env_ipath;
std::string opt_ipath;
std::string ipath;
std::string filename;
bool opt_display = true;
// Get the visp-images-data package path or VISP_INPUT_IMAGE_PATH
// environment variable value
// Set the default input path
if (!env_ipath.empty())
ipath = env_ipath;
// Read the command line options
if (getOptions(argc, argv, opt_ipath, opt_display) == false) {
// Get the option values
if (!opt_ipath.empty())
ipath = opt_ipath;
// Compare ipath and env_ipath. If they differ, we take into account
// the input path coming from the command line option
if (!opt_ipath.empty() && !env_ipath.empty()) {
if (ipath != env_ipath) {
std::cout << std::endl << "WARNING: " << std::endl;
std::cout << " Since -i <visp image path=" << ipath << "> "
<< " is different from VISP_INPUT_IMAGE_PATH=" << env_ipath << std::endl
<< " we skip the environment variable." << std::endl;
// Test if an input path is set
if (opt_ipath.empty() && env_ipath.empty()) {
usage(argv[0], nullptr, ipath);
std::cerr << std::endl << "ERROR:" << std::endl;
std::cerr << " Use -i <visp image path> option or set VISP_INPUT_IMAGE_PATH " << std::endl
<< " environment variable to specify the location of the " << std::endl
<< " image path where test images are located." << std::endl
<< std::endl;
fMo[2][3] = 0;
if (opt_display) {
simu.initInternalViewer(300, 300);
simu.initExternalViewer(300, 300);
// Load the cad model
filename = vpIoTools::createFilePath(ipath, "iv/circle.iv");
simu.load(filename.c_str(), fMo);
catch (const vpException &e) {
std::cout << "Catch an exception: " << e << std::endl;
int main()
std::cout << "You do not have Coin3D and SoQT or SoWin or SoXt functionalities enabled..." << std::endl;
std::cout << "Tip:" << std::endl;
<< "- Install Coin3D and SoQT or SoWin or SoXt, configure ViSP again using cmake and build again this example"
<< std::endl;
Generic class defining intrinsic camera parameters.
Class that defines a 3D circle in the object frame and allows forward projection of a 3D circle in th...
Definition: vpCircle.h:86
void setWorldCoordinates(const vpColVector &oP) vp_override
Definition: vpCircle.cpp:57
Implementation of column vector and the associated operations.
Definition: vpColVector.h:163
error that can be emitted by ViSP classes.
Definition: vpException.h:59
static void create(vpFeaturePoint &s, const vpCameraParameters &cam, const vpDot &d)
Class that defines 2D ellipse visual feature.
void track(const vpHomogeneousMatrix &cMo)
Implementation of an homogeneous matrix and operations on such kind of matrices.
vpHomogeneousMatrix inverse() const
static std::string getViSPImagesDataPath()
Definition: vpIoTools.cpp:1795
static std::string createFilePath(const std::string &parent, const std::string &child)
Definition: vpIoTools.cpp:2156
static double rad(double deg)
Definition: vpMath.h:127
static bool parse(int *argcPtr, const char **argv, vpArgvInfo *argTable, int flags)
Definition: vpParseArgv.cpp:69
Implementation of a pose vector and operations on poses.
Definition: vpPoseVector.h:189
void setVelocity(const vpRobot::vpControlFrameType frame, const vpColVector &vel) vp_override
Definition: vpRobot.h:82
void setMaxTranslationVelocity(double maxVt)
Definition: vpRobot.cpp:236
void setInteractionMatrixType(const vpServoIteractionMatrixType &interactionMatrixType, const vpServoInversionType &interactionMatrixInversion=PSEUDO_INVERSE)
Definition: vpServo.cpp:378
Definition: vpServo.h:155
void addFeature(vpBasicFeature &s_cur, vpBasicFeature &s_star, unsigned int select=vpBasicFeature::FEATURE_ALL)
Definition: vpServo.cpp:329
unsigned int getTaskRank() const
Definition: vpServo.h:600
void print(const vpServo::vpServoPrintType display_level=ALL, std::ostream &os=std::cout)
Definition: vpServo.cpp:169
void setLambda(double c)
Definition: vpServo.h:976
void setServo(const vpServoType &servo_type)
Definition: vpServo.cpp:132
vpColVector computeControlLaw()
Definition: vpServo.cpp:703
Definition: vpServo.h:196
Class that defines the simplest robot: a free flying camera.
Implementation of a simulator based on Coin3d (
Definition: vpSimulator.h:99
void load(const char *file_name)
load an iv file
void setInternalCameraParameters(vpCameraParameters &cam)
set internal camera parameters
virtual void mainLoop()
activate the mainloop
void initMainApplication()
perform some initialization in the main program thread
void initApplication(void *(*start_routine)(void *))
begin the main program
void setZoomFactor(float zoom)
set the size of the camera/frame
void setCameraPosition(vpHomogeneousMatrix &cMf)
set the camera position (from an homogeneous matrix)
void initExternalViewer(unsigned int nlig, unsigned int ncol)
initialize the external view
void write(const char *fileName)
virtual void initInternalViewer(unsigned int nlig, unsigned int ncol)
initialize the camera view
void closeMainApplication()
void addAbsoluteFrame(float zoom=1)
Add the representation of the absolute frame.
void display(vpImage< unsigned char > &I, const std::string &title)
Display a gray-scale image.
VISP_EXPORT int wait(double t0, double t)
VISP_EXPORT double measureTimeMs()