Joint Position Controller. More...

#include <joint_position_controller.h>

Inheritance diagram for velocity_controllers::JointPositionController:

Classes
struct	Commands
	Store position and velocity command in struct to allow easier realtime buffer usage. More...

Public Member Functions
void	getGains (double &p, double &i, double &d, double &i_max, double &i_min)
	Get the PID parameters. More...

void	getGains (double &p, double &i, double &d, double &i_max, double &i_min, bool &antiwindup)
	Get the PID parameters. More...

std::string	getJointName ()
	Get the name of the joint this controller uses. More...

double	getPosition ()
	Get the current position of the joint. More...

bool	init (hardware_interface::VelocityJointInterface *robot, ros::NodeHandle &n)
	The init function is called to initialize the controller from a non-realtime thread with a pointer to the hardware interface, itself, instead of a pointer to a RobotHW. More...

	JointPositionController ()

void	printDebug ()
	Print debug info to console. More...

void	setCommand (double pos_target)
	Give set position of the joint for next update: revolute (angle) and prismatic (position) More...

void	setCommand (double pos_target, double vel_target)
	Give set position of the joint for next update: revolute (angle) and prismatic (position) Also supports a target velocity. More...

void	setGains (const double &p, const double &i, const double &d, const double &i_max, const double &i_min, const bool &antiwindup=false)
	Get the PID parameters. More...

void	starting (const ros::Time &time)
	This is called from within the realtime thread just before the first call to update. More...

void	update (const ros::Time &time, const ros::Duration &period)
	Issues commands to the joint. Should be called at regular intervals. More...

	~JointPositionController ()

Public Member Functions inherited from controller_interface::Controller< hardware_interface::VelocityJointInterface >
	Controller ()

virtual bool	init (hardware_interface::VelocityJointInterface *, ros::NodeHandle &, ros::NodeHandle &)

virtual	~Controller ()

Public Member Functions inherited from controller_interface::ControllerBase
	ControllerBase ()

bool	isRunning ()

bool	isRunning ()

bool	startRequest (const ros::Time &time)

bool	startRequest (const ros::Time &time)

virtual void	stopping (const ros::Time &)

virtual void	stopping (const ros::Time &)

bool	stopRequest (const ros::Time &time)

bool	stopRequest (const ros::Time &time)

void	updateRequest (const ros::Time &time, const ros::Duration &period)

void	updateRequest (const ros::Time &time, const ros::Duration &period)

virtual	~ControllerBase ()

Public Attributes
realtime_tools::RealtimeBuffer< Commands >	command_

Commands	command_struct_

hardware_interface::JointHandle	joint_

urdf::JointConstSharedPtr	joint_urdf_

Public Attributes inherited from controller_interface::ControllerBase
	CONSTRUCTED

	INITIALIZED

	RUNNING

enum controller_interface::ControllerBase:: { ... }	state_

Private Member Functions
void	enforceJointLimits (double &command)
	Check that the command is within the hard limits of the joint. Checks for joint type first. Sets command to limit if out of bounds. More...

void	setCommandCB (const std_msgs::Float64ConstPtr &msg)
	Callback from /command subscriber for setpoint. More...

Private Attributes
boost::scoped_ptr< realtime_tools::RealtimePublisher< control_msgs::JointControllerState > >	controller_state_publisher_

int	loop_count_

control_toolbox::Pid	pid_controller_

ros::Subscriber	sub_command_

Additional Inherited Members
Public Types inherited from controller_interface::ControllerBase
typedef std::vector< hardware_interface::InterfaceResources >	ClaimedResources

Protected Member Functions inherited from controller_interface::Controller< hardware_interface::VelocityJointInterface >
std::string	getHardwareInterfaceType () const

virtual bool	initRequest (hardware_interface::RobotHW *robot_hw, ros::NodeHandle &root_nh, ros::NodeHandle &controller_nh, ClaimedResources &claimed_resources)

Detailed Description

Joint Position Controller.

This class controls positon using a pid loop.

ROS

Parameters

type	Must be "velocity_controllers::JointPositionController"
joint	Name of the joint to control.
pid	Contains the gains for the PID loop around position. See: control_toolbox::Pid

Subscribes to:

command (std_msgs::Float64) : The joint position to achieve.

Publishes:

state (control_msgs::JointControllerState) : Current state of the controller, including pid error and gains.

Definition at line 85 of file joint_position_controller.h.

Constructor & Destructor Documentation

velocity_controllers::JointPositionController::JointPositionController ( )

Definition at line 49 of file joint_position_controller.cpp.

velocity_controllers::JointPositionController::~JointPositionController ( )

Definition at line 53 of file joint_position_controller.cpp.

Member Function Documentation

void velocity_controllers::JointPositionController::enforceJointLimits ( double & command )

private

Check that the command is within the hard limits of the joint. Checks for joint type first. Sets command to limit if out of bounds.

Parameters

command - the input to test

Definition at line 254 of file joint_position_controller.cpp.

void velocity_controllers::JointPositionController::getGains	(	double &	p,
		double &	i,
		double &	d,
		double &	i_max,
		double &	i_min
	)

Get the PID parameters.

Definition at line 104 of file joint_position_controller.cpp.

void velocity_controllers::JointPositionController::getGains	(	double &	p,
		double &	i,
		double &	d,
		double &	i_max,
		double &	i_min,
		bool &	antiwindup
	)

Get the PID parameters.

Definition at line 110 of file joint_position_controller.cpp.

std::string velocity_controllers::JointPositionController::getJointName ( )

Get the name of the joint this controller uses.

Definition at line 120 of file joint_position_controller.cpp.

double velocity_controllers::JointPositionController::getPosition ( )

Get the current position of the joint.

Returns: current position

Definition at line 125 of file joint_position_controller.cpp.

bool velocity_controllers::JointPositionController::init	(	hardware_interface::VelocityJointInterface *	robot,
		ros::NodeHandle &	n
	)

virtual

The init function is called to initialize the controller from a non-realtime thread with a pointer to the hardware interface, itself, instead of a pointer to a RobotHW.

Parameters

robot	The specific hardware interface used by this controller.
n	A NodeHandle in the namespace from which the controller should read its configuration, and where it should set up its ROS interface.

Returns: True if initialization was successful and the controller is ready to be started.

Reimplemented from controller_interface::Controller< hardware_interface::VelocityJointInterface >.

Definition at line 58 of file joint_position_controller.cpp.

void velocity_controllers::JointPositionController::printDebug ( )

Print debug info to console.

Definition at line 115 of file joint_position_controller.cpp.

void velocity_controllers::JointPositionController::setCommand ( double pos_target )

Give set position of the joint for next update: revolute (angle) and prismatic (position)

Parameters

command

Definition at line 131 of file joint_position_controller.cpp.

void velocity_controllers::JointPositionController::setCommand	(	double	pos_target,
		double	vel_target
	)

Give set position of the joint for next update: revolute (angle) and prismatic (position) Also supports a target velocity.

Parameters

pos_target	- position setpoint
vel_target	- velocity setpoint

Definition at line 143 of file joint_position_controller.cpp.

void velocity_controllers::JointPositionController::setCommandCB ( const std_msgs::Float64ConstPtr & msg )

private

Callback from /command subscriber for setpoint.

Definition at line 248 of file joint_position_controller.cpp.

void velocity_controllers::JointPositionController::setGains	(	const double &	p,
		const double &	i,
		const double &	d,
		const double &	i_max,
		const double &	i_min,
		const bool &	antiwindup = `false`
	)

Get the PID parameters.

Definition at line 99 of file joint_position_controller.cpp.

void velocity_controllers::JointPositionController::starting ( const ros::Time & time )

virtual

This is called from within the realtime thread just before the first call to update.

Parameters

time	The current time

Reimplemented from controller_interface::ControllerBase.

Definition at line 152 of file joint_position_controller.cpp.

void velocity_controllers::JointPositionController::update	(	const ros::Time &	time,
		const ros::Duration &	period
	)

virtual

Issues commands to the joint. Should be called at regular intervals.

Implements controller_interface::ControllerBase.

Definition at line 167 of file joint_position_controller.cpp.

Member Data Documentation

realtime_tools::RealtimeBuffer<Commands> velocity_controllers::JointPositionController::command_

Definition at line 178 of file joint_position_controller.h.

Commands velocity_controllers::JointPositionController::command_struct_

Definition at line 179 of file joint_position_controller.h.

boost::scoped_ptr< realtime_tools::RealtimePublisher< control_msgs::JointControllerState> > velocity_controllers::JointPositionController::controller_state_publisher_

private

Definition at line 187 of file joint_position_controller.h.

hardware_interface::JointHandle velocity_controllers::JointPositionController::joint_

Definition at line 176 of file joint_position_controller.h.

urdf::JointConstSharedPtr velocity_controllers::JointPositionController::joint_urdf_

Definition at line 177 of file joint_position_controller.h.

int velocity_controllers::JointPositionController::loop_count_

private

Definition at line 182 of file joint_position_controller.h.

control_toolbox::Pid velocity_controllers::JointPositionController::pid_controller_

private

Internal PID controller.