ViSP  2.8.0

#include <vpRobotCamera.h>

+ Inheritance diagram for vpRobotCamera:

Public Types

enum  vpRobotStateType { STATE_STOP, STATE_VELOCITY_CONTROL, STATE_POSITION_CONTROL, STATE_ACCELERATION_CONTROL }
 
enum  vpControlFrameType { REFERENCE_FRAME, ARTICULAR_FRAME, CAMERA_FRAME, MIXT_FRAME }
 

Public Member Functions

 vpRobotCamera ()
 
virtual ~vpRobotCamera ()
 
void get_cVe (vpVelocityTwistMatrix &cVe)
 
void get_eJe (vpMatrix &eJe)
 
void getPosition (vpHomogeneousMatrix &cMw) const
 
void getPosition (const vpRobot::vpControlFrameType frame, vpColVector &q)
 
void setPosition (const vpHomogeneousMatrix &cMw)
 
void setVelocity (const vpRobot::vpControlFrameType frame, const vpColVector &v)
 
double getSamplingTime () const
 
virtual void setSamplingTime (const double &delta_t)
 
double getMaxTranslationVelocity (void) const
 
double getMaxRotationVelocity (void) const
 
vpColVector getPosition (const vpRobot::vpControlFrameType frame)
 
virtual vpRobotStateType getRobotState (void)
 
void setMaxRotationVelocity (const double maxVr)
 
void setMaxTranslationVelocity (const double maxVt)
 
virtual vpRobotStateType setRobotState (const vpRobot::vpRobotStateType newState)
 
void setVerbose (bool verbose)
 

Static Public Member Functions

static vpColVector saturateVelocities (const vpColVector &v_in, const vpColVector &v_max, bool verbose=false)
 

Protected Member Functions

vpControlFrameType setRobotFrame (vpRobot::vpControlFrameType newFrame)
 
vpControlFrameType getRobotFrame (void)
 

Protected Attributes

vpHomogeneousMatrix cMw_
 
double delta_t_
 
double maxTranslationVelocity
 
double maxRotationVelocity
 
int nDof
 
vpMatrix eJe
 
int eJeAvailable
 
vpMatrix fJe
 
int fJeAvailable
 
int areJointLimitsAvailable
 
double * qmin
 
double * qmax
 
bool verbose_
 

Static Protected Attributes

static const double maxTranslationVelocityDefault = 0.2
 
static const double maxRotationVelocityDefault = 0.7
 

Detailed Description

Class that defines the simplest robot: a free flying camera.

This free flying camera has 6 dof; 3 in translation and 3 in rotation. It evolves as a gentry robot with respect to a world frame. This class is similar to vpSimulatorCamera class except that here the position of the robot is provided as the transformation from camera frame to world frame; cMw. Since the position of the camera frame evolves, this representation is less intuitive than the one implemented in vpSimulatorCamera where the transformation from world to camera frame is considered; wMc.

Note
We recommend to use vpSimulatorCamera rather than vpRobotCamera.

For this particular simulated robot, the end-effector and camera frame are confused. That means that the cMe transformation is equal to identity.

The robot jacobian expressed in the end-effector frame $ {^e}{\bf J}_e $ is also set to identity (see get_eJe()).

The following code shows how to control this robot in position and velocity.

#include <visp/vpRobotCamera.h>
int main()
{
robot.getPosition(cMw); // Position of the camera in the world frame
std::cout << "Default position of the camera in the world frame cMw:\n" << cMw << std::endl;
cMw[2][3] = 1.; // World frame is 1 meter along z axis in front of the camera frame
robot.setPosition(cMw); // Set the new position of the camera wrt the world frame
std::cout << "New position of the camera wrt the world frame cMw:\n" << cMw << std::endl;
robot.setSamplingTime(0.100); // Modify the default sampling time to 0.1 second
robot.setMaxTranslationVelocity(1.); // vx, vy and vz max set to 1 m/s
robot.setMaxRotationVelocity(vpMath::rad(90)); // wx, wy and wz max set to 90 deg/s
v = 0;
v[2] = 1.; // set v_z to 1 m/s
// The robot has moved from 0.1 meters along the z axis
robot.getPosition(cMw); // Position of the camera wrt the world frame
std::cout << "New position of the camera cMw:\n" << cMw << std::endl;
}
Examples:
manServo4PointsDisplay.cpp, manServoMomentsSimple.cpp, manSimu4Dots.cpp, manSimu4Points.cpp, photometricVisualServoing.cpp, servoMomentImage.cpp, servoSimuCylinder.cpp, servoSimuSphere.cpp, simulateCircle2DCamVelocity.cpp, simulateFourPoints2DCartesianCamVelocity.cpp, simulateFourPoints2DPolarCamVelocity.cpp, and testFeatureSegment.cpp.

Definition at line 110 of file vpRobotCamera.h.

Member Enumeration Documentation

Robot control frames.

Enumerator
REFERENCE_FRAME 

Corresponds to a fixed reference frame attached to the robot structure.

ARTICULAR_FRAME 

Corresponds to the joint space.

CAMERA_FRAME 

Corresponds to a frame attached to the camera mounted on the robot end-effector.

MIXT_FRAME 

Corresponds to a "virtual" frame where translations are expressed in the reference frame, and rotations in the camera frame.

Definition at line 78 of file vpRobot.h.

enum vpRobot::vpRobotStateType
inherited

Robot control states.

Enumerator
STATE_STOP 

Stops robot motion especially in velocity and acceleration control.

STATE_VELOCITY_CONTROL 

Initialize the velocity controller.

STATE_POSITION_CONTROL 

Initialize the position controller.

STATE_ACCELERATION_CONTROL 

Initialize the acceleration controller.

Definition at line 66 of file vpRobot.h.

Constructor & Destructor Documentation

vpRobotCamera::vpRobotCamera ( )

Constructor.

Initialise the robot by a call to init().

Sampling time is set to 40 ms. To change it you should call setSamplingTime().

Robot jacobian expressed in the end-effector frame $ {^e}{\bf J}_e $ is set to identity (see get_eJe()).

robot.setSamplingTime(0.020); // Set the sampling time to 20 ms.

Definition at line 74 of file vpRobotCamera.cpp.

vpRobotCamera::~vpRobotCamera ( )
virtual

Destructor.

Definition at line 106 of file vpRobotCamera.cpp.

Member Function Documentation

void vpRobotCamera::get_cVe ( vpVelocityTwistMatrix cVe)

Get the twist transformation from camera frame to end-effector frame. This transformation allows to compute a velocity expressed in the end-effector frame into the camera frame.

Parameters
cVe: Twist transformation. Here this transformation is equal to identity since camera frame and end-effector frame are at the same location.
Examples:
servoBiclopsPoint2DArtVelocity.cpp.

Definition at line 121 of file vpRobotCamera.cpp.

void vpRobotCamera::get_eJe ( vpMatrix eJe)
virtual

Get the robot jacobian expressed in the end-effector frame. For that simple robot the Jacobian is the identity.

Parameters
eJe: A 6 by 6 matrix representing the robot jacobian $ {^e}{\bf J}_e$ expressed in the end-effector frame.

Implements vpRobot.

Examples:
manServo4PointsDisplay.cpp, manSimu4Dots.cpp, manSimu4Points.cpp, servoBiclopsPoint2DArtVelocity.cpp, servoSimuCylinder.cpp, servoSimuSphere.cpp, simulateFourPoints2DCartesianCamVelocity.cpp, and simulateFourPoints2DPolarCamVelocity.cpp.

Definition at line 135 of file vpRobotCamera.cpp.

References vpRobot::eJe.

double vpRobot::getMaxTranslationVelocity ( void  ) const
inherited
void vpRobotCamera::getPosition ( const vpRobot::vpControlFrameType  frame,
vpColVector q 
)
virtual
vpColVector vpRobot::getPosition ( const vpRobot::vpControlFrameType  frame)
inherited

Return the current robot position in the specified frame.

Definition at line 171 of file vpRobot.cpp.

vpControlFrameType vpRobot::getRobotFrame ( void  )
inlineprotectedinherited
double vpRobotSimulator::getSamplingTime ( ) const
inlineinherited
vpColVector vpRobot::saturateVelocities ( const vpColVector v_in,
const vpColVector v_max,
bool  verbose = false 
)
staticinherited

Saturate velocities.

Parameters
v_in: Vector of input velocities to saturate. Translation velocities should be expressed in m/s while rotation velocities in rad/s.
v_max: Vector of maximal allowed velocities. Maximal translation velocities should be expressed in m/s while maximal rotation velocities in rad/s.
verbose: Print a message indicating which axis causes the saturation.
Returns
Saturated velocities.
Exceptions
vpRobotException::dimensionError: If the input vectors have different dimensions.

The code below shows how to use this static method in order to saturate a velocity skew vector.

#include <iostream>
#include <visp/vpRobot.h>
int main()
{
// Set a velocity skew vector
v[0] = 0.1; // vx in m/s
v[1] = 0.2; // vy
v[2] = 0.3; // vz
v[3] = vpMath::rad(10); // wx in rad/s
v[4] = vpMath::rad(-10); // wy
v[5] = vpMath::rad(20); // wz
// Set the maximal allowed velocities
vpColVector v_max(6);
for (int i=0; i<3; i++)
v_max[i] = 0.3; // in translation (m/s)
for (int i=3; i<6; i++)
v_max[i] = vpMath::rad(10); // in rotation (rad/s)
// Compute the saturated velocity skew vector
vpColVector v_sat = vpRobot::saturateVelocities(v, v_max, true);
std::cout << "v : " << v.t() << std::endl;
std::cout << "v max: " << v_max.t() << std::endl;
std::cout << "v sat: " << v_sat.t() << std::endl;
return 0;
}

Definition at line 116 of file vpRobot.cpp.

References vpException::dimensionError, and vpColVector::size().

Referenced by setVelocity(), vpSimulatorCamera::setVelocity(), vpSimulatorPioneer::setVelocity(), vpRobotPioneer::setVelocity(), vpSimulatorPioneerPan::setVelocity(), vpRobotAfma4::setVelocity(), vpRobotAfma6::setVelocity(), vpRobotViper650::setVelocity(), and vpRobotViper850::setVelocity().

void vpRobot::setMaxRotationVelocity ( const double  w_max)
inherited

Set the maximal rotation velocity that can be sent to the robot during a velocity control.

Parameters
w_max: Maximum rotation velocity expressed in rad/s.
Examples:
servoMomentPoints.cpp, servoSimu4Points.cpp, and servoSimuSphere.cpp.

Definition at line 215 of file vpRobot.cpp.

Referenced by vpSimulatorAfma6::setPosition().

void vpRobot::setMaxTranslationVelocity ( const double  v_max)
inherited

Set the maximal translation velocity that can be sent to the robot during a velocity control.

Parameters
v_max: Maximum translation velocity expressed in m/s.
Examples:
servoMomentPoints.cpp, servoSimu4Points.cpp, and servoSimuSphere.cpp.

Definition at line 191 of file vpRobot.cpp.

Referenced by vpSimulatorAfma6::setPosition().

void vpRobotCamera::setVelocity ( const vpRobot::vpControlFrameType  frame,
const vpColVector v 
)
virtual

Send to the controller a velocity.

Parameters
frame: Control frame type. Only articular (vpRobot::ARTICULAR_FRAME) and camera frame (vpRobot::CAMERA_FRAME) are implemented.
v: Velocity to apply to the robot.
  • In the camera frame, this velocity is represented by a vector of dimension 6 $ {\bf v} = [{\bf t}, {\bf \theta u }]^t $ where $ \bf t $ is a translation vector and $ {\bf \theta u} $ is a rotation vector (see vpThetaUVector): $ {\bf v} = [t_x, t_y, t_z, {\theta u}_x, {\theta u}_y, {\theta u}_z] $ (see vpTranslationVector and vpThetaUVector).
  • In articular, this velocity is represented by a 6 dimension vector $ \dot{{\bf q}} = [{\bf t}, {\bf \theta u}]^t $ where $ \bf t $ is a translation vector and $ {\bf \theta u} $ is a rotation vector (see vpThetaUVector): $ \dot{{\bf q}} = [t_x, t_y, t_z, {\theta u}_x, {\theta u}_y, {\theta u}_z] $ (see vpTranslationVector and vpThetaUVector). The robot jacobian $ {^e}{\bf J}_e$ expressed in the end-effector frame is here set to identity.

We use the exponential map (vpExponentialMap) to update the camera location. Sampling time can be set using setSamplingTime().

See also
setSamplingTime()

Implements vpRobot.

Examples:
manServo4PointsDisplay.cpp, manServoMomentsSimple.cpp, manSimu4Dots.cpp, manSimu4Points.cpp, moveBiclops.cpp, photometricVisualServoing.cpp, servoBiclopsPoint2DArtVelocity.cpp, servoMomentImage.cpp, servoMomentPoints.cpp, servoSimuAfma6FourPoints2DCamVelocity.cpp, servoSimuCylinder.cpp, servoSimuSphere.cpp, servoSimuViper850FourPoints2DCamVelocity.cpp, simulateCircle2DCamVelocity.cpp, simulateFourPoints2DCartesianCamVelocity.cpp, simulateFourPoints2DPolarCamVelocity.cpp, testFeatureSegment.cpp, tutorial-ibvs-4pts-wireframe-robot-afma6.cpp, and tutorial-ibvs-4pts-wireframe-robot-viper.cpp.

Definition at line 169 of file vpRobotCamera.cpp.

References vpRobot::ARTICULAR_FRAME, vpRobot::CAMERA_FRAME, cMw_, vpRobotSimulator::delta_t_, vpExponentialMap::direct(), vpRobot::getMaxRotationVelocity(), vpRobot::getMaxTranslationVelocity(), vpRobot::getRobotState(), vpHomogeneousMatrix::inverse(), vpRobot::MIXT_FRAME, vpRobot::REFERENCE_FRAME, vpRobot::saturateVelocities(), vpRobot::setRobotState(), vpRobot::STATE_VELOCITY_CONTROL, vpERROR_TRACE, and vpRobotException::wrongStateError.

Member Data Documentation

int vpRobot::areJointLimitsAvailable
protectedinherited

Definition at line 111 of file vpRobot.h.

vpHomogeneousMatrix vpRobotCamera::cMw_
protected

Definition at line 113 of file vpRobotCamera.h.

Referenced by getPosition(), setPosition(), and setVelocity().

double vpRobotSimulator::delta_t_
protectedinherited
int vpRobot::eJeAvailable
protectedinherited

is the robot Jacobian expressed in the end-effector frame available

Definition at line 105 of file vpRobot.h.

vpMatrix vpRobot::fJe
protectedinherited

robot Jacobian expressed in the robot reference frame available

Definition at line 107 of file vpRobot.h.

Referenced by vpSimulatorAfma6::computeArticularVelocity(), vpSimulatorViper850::computeArticularVelocity(), vpSimulatorAfma6::getVelocity(), and vpSimulatorViper850::getVelocity().

int vpRobot::fJeAvailable
protectedinherited

is the robot Jacobian expressed in the robot reference frame available

Definition at line 109 of file vpRobot.h.

double vpRobot::maxRotationVelocity
protectedinherited

Definition at line 97 of file vpRobot.h.

const double vpRobot::maxRotationVelocityDefault = 0.7
staticprotectedinherited

Definition at line 98 of file vpRobot.h.

double vpRobot::maxTranslationVelocity
protectedinherited

Definition at line 95 of file vpRobot.h.

const double vpRobot::maxTranslationVelocityDefault = 0.2
staticprotectedinherited

Definition at line 96 of file vpRobot.h.

int vpRobot::nDof
protectedinherited

number of degrees of freedom

Definition at line 101 of file vpRobot.h.

double* vpRobot::qmax
protectedinherited

Definition at line 113 of file vpRobot.h.

double* vpRobot::qmin
protectedinherited

Definition at line 112 of file vpRobot.h.