Class Model

Class Documentation

class Model

Calculates poses of joints and dynamic properties of the robot.

Public Functions

explicit Model(franka::Network &network, const std::string &urdf_model)

Creates a new Model instance.

This constructor is for internal use only.

See also

Robot::loadModel

Parameters:

network – [in] For internal use.

Throws:

ModelException – if the model library cannot be loaded.

explicit Model(franka::Network &network, std::unique_ptr<RobotModelBase> robot_model)

Creates a new Model instance only for the tests.

This constructor is for the unittests for enabling mocks.

Parameters:

  • network – [in] For internal use.

  • robot_model – [in] unique pointer to the mocked robot_model

Model(Model &&model) noexcept

Move-constructs a new Model instance.

Parameters:

model – [in] Other Model instance.

Model &operator=(Model &&model) noexcept

Move-assigns this Model from another Model instance.

Parameters:

model – [in] Other Model instance.

Returns:

Model instance.

~Model() noexcept

Unloads the model library.

std::array<double, 16> pose(Frame frame, const franka::RobotState &robot_state) const

Gets the 4x4 pose matrix for the given frame in base frame.

The pose is represented as a 4x4 matrix in column-major format.

Parameters:

  • frame – [in] The desired frame.

  • robot_state – [in] State from which the pose should be calculated.

Returns:

Vectorized 4x4 pose matrix, column-major.

std::array<double, 16> pose(Frame frame, const std::array<double, 7> &q, const std::array<double, 16> &F_T_EE, const std::array<double, 16> &EE_T_K) const

Gets the 4x4 pose matrix for the given frame in base frame.

The pose is represented as a 4x4 matrix in column-major format.

Parameters:

  • frame – [in] The desired frame.

  • q – [in] Joint position.

  • F_T_EE – [in] End effector in flange frame.

  • EE_T_K – [in] Stiffness frame K in the end effector frame.

Returns:

Vectorized 4x4 pose matrix, column-major.

std::array<double, 42> bodyJacobian(Frame frame, const franka::RobotState &robot_state) const

Gets the 6x7 Jacobian for the given frame, relative to that frame.

The Jacobian is represented as a 6x7 matrix in column-major format.

Parameters:

  • frame – [in] The desired frame.

  • robot_state – [in] State from which the pose should be calculated.

Returns:

Vectorized 6x7 Jacobian, column-major.

std::array<double, 42> bodyJacobian(Frame frame, const std::array<double, 7> &q, const std::array<double, 16> &F_T_EE, const std::array<double, 16> &EE_T_K) const

Gets the 6x7 Jacobian for the given frame, relative to that frame.

The Jacobian is represented as a 6x7 matrix in column-major format.

Parameters:

  • frame – [in] The desired frame.

  • q – [in] Joint position.

  • F_T_EE – [in] End effector in flange frame.

  • EE_T_K – [in] Stiffness frame K in the end effector frame.

Returns:

Vectorized 6x7 Jacobian, column-major.

std::array<double, 42> zeroJacobian(Frame frame, const franka::RobotState &robot_state) const

Gets the 6x7 Jacobian for the given joint relative to the base frame.

The Jacobian is represented as a 6x7 matrix in column-major format.

Parameters:

  • frame – [in] The desired frame.

  • robot_state – [in] State from which the pose should be calculated.

Returns:

Vectorized 6x7 Jacobian, column-major.

std::array<double, 42> zeroJacobian(Frame frame, const std::array<double, 7> &q, const std::array<double, 16> &F_T_EE, const std::array<double, 16> &EE_T_K) const

Gets the 6x7 Jacobian for the given joint relative to the base frame.

The Jacobian is represented as a 6x7 matrix in column-major format.

Parameters:

  • frame – [in] The desired frame.

  • q – [in] Joint position.

  • F_T_EE – [in] End effector in flange frame.

  • EE_T_K – [in] Stiffness frame K in the end effector frame.

Returns:

Vectorized 6x7 Jacobian, column-major.

std::array<double, 49> mass(const franka::RobotState &robot_state) const noexcept

Calculates the 7x7 mass matrix. Unit: \([kg \times m^2]\).

Parameters:

robot_state – [in] State from which the mass matrix should be calculated.

Returns:

Vectorized 7x7 mass matrix, column-major.

std::array<double, 49> mass(const std::array<double, 7> &q, const std::array<double, 9> &I_total, double m_total, const std::array<double, 3> &F_x_Ctotal) const noexcept

Calculates the 7x7 mass matrix. Unit: \([kg \times m^2]\).

Parameters:

  • q – [in] Joint position.

  • I_total – [in] Inertia of the attached total load including end effector, relative to center of mass, given as vectorized 3x3 column-major matrix. Unit: \([kg \times m^2]\).

  • m_total – [in] Weight of the attached total load including end effector. Unit: \([kg]\).

  • F_x_Ctotal – [in] Translation from flange to center of mass of the attached total load. Unit: \([m]\).

Returns:

Vectorized 7x7 mass matrix, column-major.

std::array<double, 7> coriolis(const franka::RobotState &robot_state) const noexcept

Calculates the Coriolis force vector (state-space equation): \( c= C \times dq\), in \([Nm]\).

Parameters:

robot_state – [in] State from which the Coriolis force vector should be calculated.

Returns:

Coriolis force vector.

std::array<double, 7> coriolis(const std::array<double, 7> &q, const std::array<double, 7> &dq, const std::array<double, 9> &I_total, double m_total, const std::array<double, 3> &F_x_Ctotal) const noexcept

Calculates the Coriolis force vector (state-space equation): \( c= C \times dq\), in \([Nm]\).

Parameters:

  • q – [in] Joint position.

  • dq – [in] Joint velocity.

  • I_total – [in] Inertia of the attached total load including end effector, relative to center of mass, given as vectorized 3x3 column-major matrix. Unit: \([kg \times m^2]\).

  • m_total – [in] Weight of the attached total load including end effector. Unit: \([kg]\).

  • F_x_Ctotal – [in] Translation from flange to center of mass of the attached total load. Unit: \([m]\).

Returns:

Coriolis force vector.

std::array<double, 7> gravity(const std::array<double, 7> &q, double m_total, const std::array<double, 3> &F_x_Ctotal, const std::array<double, 3> &gravity_earth = {{0., 0., -9.81}}) const noexcept

Calculates the gravity vector. Unit: \([Nm]\).

Parameters:

  • q – [in] Joint position.

  • m_total – [in] Weight of the attached total load including end effector. Unit: \([kg]\).

  • F_x_Ctotal – [in] Translation from flange to center of mass of the attached total load. Unit: \([m]\).

  • gravity_earth – [in] Earth’s gravity vector. Unit: \(\frac{m}{s^2}\). Default to {0.0, 0.0, -9.81}.

Returns:

Gravity vector.

std::array<double, 7> gravity(const franka::RobotState &robot_state, const std::array<double, 3> &gravity_earth) const noexcept

Calculates the gravity vector. Unit: \([Nm]\).

Parameters:

  • robot_state – [in] State from which the gravity vector should be calculated.

  • gravity_earth – [in] Earth’s gravity vector. Unit: \(\frac{m}{s^2}\).

Returns:

Gravity vector.

std::array<double, 7> gravity(const franka::RobotState &robot_state) const noexcept

Calculates the gravity vector using the robot state. Unit: \([Nm]\).

Parameters:

robot_state – [in] State from which the gravity vector should be calculated.

Returns:

Gravity vector.