Example of eye-in-hand control law. We control here a real robot, the Afma4 robot (cylindrical robot, with 4 degrees of freedom). The velocity is computed in the camera frame. The visual feature is the center of gravity of a point.In this example we estimate the velocity of the target in order to reduce the tracking error when the target is moving. The velocity of the target is filtered by a Kalman filter with a constant velocity state model, or a constant acceleration state model.
#include <stdlib.h>
#include <visp3/core/vpConfig.h>
#include <visp3/core/vpDebug.h>
#if (defined(VISP_HAVE_AFMA4) && defined(VISP_HAVE_DC1394))
#include <visp3/core/vpDisplay.h>
#include <visp3/core/vpImage.h>
#include <visp3/gui/vpDisplayGTK.h>
#include <visp3/gui/vpDisplayOpenCV.h>
#include <visp3/gui/vpDisplayX.h>
#include <visp3/sensor/vp1394TwoGrabber.h>
#include <visp3/blob/vpDot2.h>
#include <visp3/core/vpException.h>
#include <visp3/core/vpHomogeneousMatrix.h>
#include <visp3/core/vpIoTools.h>
#include <visp3/core/vpLinearKalmanFilterInstantiation.h>
#include <visp3/core/vpMath.h>
#include <visp3/core/vpPoint.h>
#include <visp3/io/vpParseArgv.h>
#include <visp3/robot/vpRobotAfma4.h>
#include <visp3/visual_features/vpFeatureBuilder.h>
#include <visp3/visual_features/vpFeaturePoint.h>
#include <visp3/vs/vpAdaptiveGain.h>
#include <visp3/vs/vpServo.h>
#include <visp3/vs/vpServoDisplay.h>
#define GETOPTARGS "hK:l:"
typedef enum { K_NONE, K_VELOCITY, K_ACCELERATION } KalmanType;
void usage(const char *name, const char *badparam, KalmanType &kalman)
{
fprintf(stdout, "\n\
Tests a control law with the following characteristics:\n\
- eye-in-hand control\n\
- camera velocity are computed\n\
- servo on 1 points.\n\
- Kalman filtering\n\
\n\
SYNOPSIS\n\
%s [-K <0|1|2|3>] [-h]\n", name);
fprintf(stdout, "\n\
OPTIONS: Default\n\
-l <%%f> \n\
Set the constant gain. By default adaptive gain. \n\
\n\
-K <0|1|2> %d\n\
Kalman filtering:\n\
0: none\n\
1: velocity model\n\
2: acceleration model\n\
\n\
-h\n\
Print the help.\n", (int)kalman);
if (badparam) {
fprintf(stderr, "ERROR: \n");
fprintf(stderr, "\nBad parameter [%s]\n", badparam);
}
}
bool getOptions(int argc, const char **argv, KalmanType &kalman, bool &doAdaptativeGain,
{
const char *optarg;
int c;
switch (c) {
case 'K':
kalman = (KalmanType)atoi(optarg);
break;
case 'l':
doAdaptativeGain = false;
break;
case 'h':
usage(argv[0], NULL, kalman);
return false;
break;
default:
usage(argv[0], optarg, kalman);
return false;
break;
}
}
if ((c == 1) || (c == -1)) {
usage(argv[0], NULL, kalman);
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)
{
try {
KalmanType opt_kalman = K_NONE;
bool doAdaptativeGain = true;
int opt_cam_frequency = 60;
if (getOptions(argc, argv, opt_kalman, doAdaptativeGain, lambda) == false) {
return (-1);
}
std::string username;
std::string logdirname;
logdirname = "/tmp/" + username;
try {
} catch (...) {
std::cerr << std::endl << "ERROR:" << std::endl;
std::cerr << " Cannot create " << logdirname << std::endl;
exit(-1);
}
}
std::string logfilename;
logfilename = logdirname + "/log.dat";
std::ofstream flog(logfilename.c_str());
switch (opt_cam_frequency) {
case 15:
break;
case 30:
break;
case 60:
break;
}
for (int i = 0; i < 10; i++)
#ifdef VISP_HAVE_X11
#elif defined(VISP_HAVE_OPENCV)
#elif defined(VISP_HAVE_GTK)
#endif
std::cout << std::endl;
std::cout << "-------------------------------------------------------" << std::endl;
std::cout << "Test program for target motion compensation using a Kalman "
"filter "
<< std::endl;
std::cout << "Eye-in-hand task control, velocity computed in the camera frame" << std::endl;
std::cout << "Task : servo a point \n" << std::endl;
switch (opt_kalman) {
case K_NONE:
std::cout << "Servo with no target motion compensation (see -K option)\n";
break;
case K_VELOCITY:
std::cout << "Servo with target motion compensation using a Kalman filter\n"
<< "with constant velocity modelization (see -K option)\n";
break;
case K_ACCELERATION:
std::cout << "Servo with target motion compensation using a Kalman filter\n"
<< "with constant acceleration modelization (see -K option)\n";
break;
}
std::cout << "-------------------------------------------------------" << std::endl;
std::cout << std::endl;
std::cout << "Click on the dot..." << std::endl;
double px = 1000;
double py = 1000;
std::cout << std::endl;
task.addFeature(p, pd);
task.setLambda(lambda);
unsigned int nsignal = 2;
double rho = 0.3;
unsigned int state_size = 0;
switch (opt_kalman) {
case K_VELOCITY: {
sigma_state.
resize(state_size * nsignal);
sigma_state = 0.00001;
sigma_measure = 0.05;
double dummy = 0;
kalman.
initFilter(nsignal, sigma_state, sigma_measure, rho, dummy);
break;
}
case K_ACCELERATION: {
sigma_state.
resize(state_size * nsignal);
sigma_state = 0.00001;
sigma_measure = 0.05;
double dt = 1. / opt_cam_frequency;
kalman.
initFilter(nsignal, sigma_state, sigma_measure, rho, dt);
break;
}
default:
break;
}
int iter = 0;
double t_1, Tv_0;
Tv_0 = 0;
std::cout << "\nHit CTRL-C to stop the loop...\n" << std::flush;
for (;;) {
double Tv = (double)(t_0 - t_1) / 1000.0;
t_1 = t_0;
vm_0 = vm;
double Tv_1 = Tv_0;
Tv_0 = Tv;
v1 = task.computeControlLaw();
err = task.error;
if (iter == 0) {
err_0 = 0;
err_1 = 0;
dedt_mes = 0;
dedt_filt = 0;
} else {
err_1 = err_0;
err_0 = err;
dedt_mes = (err_0 - err_1) / (Tv_1)-task.J1 * vm_0;
}
if (iter <= 1) {
dedt_mes = 0;
}
switch (opt_kalman) {
case K_NONE:
dedt_filt = 0;
break;
case K_VELOCITY:
case K_ACCELERATION:
for (unsigned int i = 0; i < nsignal; i++) {
dedt_filt[i] = kalman.
Xest[i * state_size];
}
break;
}
vpMatrix J1p = task.getTaskJacobianPseudoInverse();
v2 = -J1p * dedt_filt;
v = v1 + v2;
flog << Tv_0 << " ";
flog << v[0] << " " << v[1] << " " << v[2] << " " << v[3] << " " << v[4] << " " << v[5] << " ";
flog << task.error[0] << " " << task.error[1] << " ";
flog << dedt_mes[0] << " " << dedt_mes[1] << " ";
flog << dedt_filt[0] << " " << dedt_filt[1] << " ";
flog << std::endl;
iter++;
}
flog.close();
task.print();
task.kill();
return EXIT_SUCCESS;
std::cout << "Catch a ViSP exception: " << e << std::endl;
return EXIT_FAILURE;
}
}
#else
int main()
{
std::cout << "You do not have an afma4 robot connected to your computer..." << std::endl;
return EXIT_SUCCESS;
}
#endif