BipedalLocomotion::IK::CoMTask class
#include <BipedalLocomotion/IK/CoMTask.h>

SE3Task is a concrete implementation of the Task.

Please use this element if you want to control the position and the orientation of a given frame rigidly attached to the robot. The task assumes perfect control of the robot velocity that contains the base linear and angular velocity expressed in mixed representation and the joint velocities. The task represents the following equation

where is the robot jacobian and is the desired velocity. The desired velocity is chosen such that the frame will asymptotically converge to the desired trajectory. The linear component of is computed with a standard Proportional controller in while the angular velocity is computed by a Proportional controller in .

Base classes

struct IKLinearTask: IKLinearTask specializes a LinearTask in the case of Inverse Kinematics.

Public functions

auto initialize(std::weak_ptr<const ParametersHandler::IParametersHandler> paramHandler) -> bool override: Initialize the task.
auto setKinDyn(std::shared_ptr<iDynTree::KinDynComputations> kinDyn) -> bool override: Set the kinDynComputations object.
auto setVariablesHandler(const System::VariablesHandler& variablesHandler) -> bool override: Set the set of variables required by the task.
auto update() -> bool override: Update the content of the element.
auto setSetPoint(Eigen::Ref<const Eigen::Vector3d> position, Eigen::Ref<const Eigen::Vector3d> velocity) -> bool: Set the desired set-point of the trajectory.
auto size() const -> std::size_t override: Get the size of the task.
auto type() const -> Type override: The CoMTask is an equality task.
auto isValid() const -> bool override: Determines the validity of the objects retrieved with getA() and getB()
auto setFeedback(Eigen::Ref<const Eigen::Vector3d> comPosition) -> bool: Set the feedback for the Proportional controller.

Function documentation

bool BipedalLocomotion::IK::CoMTask::initialize(std::weak_ptr<const ParametersHandler::IParametersHandler> paramHandler) override

Initialize the task.

Parameters
paramHandler	pointer to the parameters handler.
Returns	True in case of success, false otherwise. Where the generalized robot velocity is a vector containing the base spatial-velocity (expressed in mixed representation) and the joint velocities.

Note

the following parameters are required by the class

Parameter Name	Type	Description	Mandatory
`robot_velocity_variable_name`	`string`	Name of the variable contained in `VariablesHandler` describing the robot velocity	Yes
`kp_linear`	`double` or `vector<double>`	Gain of the position controller	Yes
`mask`	`vector<bool>`	Mask representing the DoFs controlled. E.g. [1,0,1] will enable the control on the x and z coordinates only. (Default value, [1,1,1])	No
`use_exogenous_feedback`	`bool`	If true the task will consider the CoM position provided by the user as feedback. The feedback must be set using `setFeedback()`. (Default value `false`)	No

bool BipedalLocomotion::IK::CoMTask::setKinDyn(std::shared_ptr<iDynTree::KinDynComputations> kinDyn) override

Set the kinDynComputations object.

Parameters
kinDyn	pointer to a kinDynComputations object.
Returns	True in case of success, false otherwise.

bool BipedalLocomotion::IK::CoMTask::setVariablesHandler(const System::VariablesHandler& variablesHandler) override

Set the set of variables required by the task.

Parameters
variablesHandler	reference to a variables handler.
Returns	True in case of success, false otherwise.

The variables are stored in the System::VariablesHandler.

bool BipedalLocomotion::IK::CoMTask::update() override

Update the content of the element.

Returns	True in case of success, false otherwise.

bool BipedalLocomotion::IK::CoMTask::setSetPoint(Eigen::Ref<const Eigen::Vector3d> position, Eigen::Ref<const Eigen::Vector3d> velocity)

Set the desired set-point of the trajectory.

Parameters
position	position of the CoM
velocity	velocity of the CoM expressed in mixed representation
Returns	True in case of success, false otherwise.

std::size_t BipedalLocomotion::IK::CoMTask::size() const override

Get the size of the task.

Returns	the size of the task.

(I.e the number of rows of the vector b)

Type BipedalLocomotion::IK::CoMTask::type() const override

The CoMTask is an equality task.

Returns	the size of the task.

bool BipedalLocomotion::IK::CoMTask::isValid() const override

Determines the validity of the objects retrieved with getA() and getB()

Returns	True if the objects are valid, false otherwise.

bool BipedalLocomotion::IK::CoMTask::setFeedback(Eigen::Ref<const Eigen::Vector3d> comPosition)

Set the feedback for the Proportional controller.

Parameters
comPosition	position of the CoM respect to the inertial frame.
Returns	True in case of success, false otherwise.