wbc::JointPosPDController Class Reference

The JointPosPDController class implements a PD Controller with feed forward on the base-Joints type. The following control schemes are available: More...

#include <JointPosPDController.hpp>

Inheritance diagram for wbc::JointPosPDController:

Public Member Functions
	JointPosPDController (const std::vector< std::string > &joint_names)
const base::commands::Joints &	update (const base::commands::Joints &setpoint, const base::samples::Joints &feedback)
Public Member Functions inherited from wbc::PosPDController
	PosPDController (size_t dim_controller)
void	update ()
void	setPGain (const base::VectorXd &gain)
const base::VectorXd &	pGain ()
void	setDGain (const base::VectorXd &gain)
const base::VectorXd &	dGain ()
void	setFFGain (const base::VectorXd &gain)
const base::VectorXd &	ffGain ()
void	setMaxCtrlOutput (const base::VectorXd &max_ctrl_out)
const base::VectorXd &	maxCtrlOutput ()
void	setDeadZone (const base::VectorXd &dz)
const base::VectorXd &	deadZone ()
base::VectorXd	getControlError ()
void	applySaturation (const base::VectorXd &in, const base::VectorXd &max, base::VectorXd &out)
	Apply Saturation on the control output. If one or more values of <in> are bigger than the Corrresponding entry of <max>, all values will be scaled down according to the biggest ratio eta = in_i / max,i.
void	applyDeadZone (const base::VectorXd &in, const base::VectorXd &min, base::VectorXd &out)
	Apply dead zone, i.e. minimum position control error. If one of the input value falls below minimum, it will be set to zero. Otherwise dead zone will be subtracted from the input value, to get a smooth transition:

Protected Member Functions
void	extractFeedback (const base::samples::Joints &feedback)
void	extractSetpoint (const base::commands::Joints &setpoint)

Protected Attributes
base::commands::Joints	control_output
std::vector< std::string >	joint_names
Protected Attributes inherited from wbc::PosPDController
size_t	dim_controller
base::VectorXd	p_gain
base::VectorXd	d_gain
base::VectorXd	ff_gain
base::VectorXd	dead_zone
base::VectorXd	max_control_output
base::VectorXd	ref_pos
base::VectorXd	ref_vel
base::VectorXd	ref_acc
base::VectorXd	pos
base::VectorXd	vel
base::VectorXd	acc
base::VectorXd	pos_diff
base::VectorXd	vel_diff
base::VectorXd	control_out_vel
base::VectorXd	control_out_acc

Detailed Description

The JointPosPDController class implements a PD Controller with feed forward on the base-Joints type. The following control schemes are available:

1. Velocity Output: \(\dot{\mathbf{q}}_d = \mathbf{K}_d\dot{\mathbf{q}}_r + \mathbf{K}_pe\)
2. Acceleration Output: \(\ddot{\mathbf{q}}_d = \mathbf{K}_{ff}\ddot{\mathbf{e}} + \mathbf{K}_d\dot{\mathbf{e}} + \mathbf{K}_p\mathbf{e}\),

where \( \mathbf{e} = \mathbf{q}_r-\mathbf{q} \), \( \dot{\mathbf{e}} = \dot{\mathbf{q}}_r-\dot{\mathbf{q}} \) and \( \ddot{\mathbf{e}} = \ddot{\mathbf{q}}_r-\ddot{\mathbf{q}} \)

\( \mathbf{q},\mathbf{q}_r \) - Actual and reference joint position
\( \dot{\mathbf{q}},\dot{\mathbf{q}}_r \) - Actual and reference joint velocity
\( \ddot{\mathbf{q}},\ddot{\mathbf{q}}_r \) - Actual and reference joint acceleration
\( \mathbf{K}_d,\mathbf{K}_p \) - Derivative and proportial gain matrices
\( \mathbf{K}_{ff} \) - Feed forward gain matrix
\( \ddot{\mathbf{q}}_d,\dot{\mathbf{q}}_d \) - Control output, desired acceleration or velocity

Note: If an input is NaN, it might be ignored by the controller. E.g. if the reference or actual velocity is none, the velocity error will be set to zero in the controller

Constructor & Destructor Documentation

JointPosPDController()

wbc::JointPosPDController::JointPosPDController

(

const std::vector< std::string > &

joint_names

)

Member Function Documentation

extractFeedback()

void wbc::JointPosPDController::extractFeedback ( const base::samples::Joints & feedback )

protected

extractSetpoint()

void wbc::JointPosPDController::extractSetpoint ( const base::commands::Joints & setpoint )

protected

update()

const base::commands::Joints & wbc::JointPosPDController::update	(	const base::commands::Joints &	setpoint,
		const base::samples::Joints &	feedback )

Convert typed to raw input data and call PosPDController::update()

Member Data Documentation

control_output

base::commands::Joints wbc::JointPosPDController::control_output

protected

joint_names

std::vector<std::string> wbc::JointPosPDController::joint_names

protected

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The documentation for this class was generated from the following files:

• src/controllers/JointPosPDController.hpp
• src/controllers/JointPosPDController.cpp