arl::controller::GravityCompensation Class Reference

Implements a gravity compensation controller. More...

#include <gravity_compensation.h>

Inheritance diagram for arl::controller::GravityCompensation:

Collaboration diagram for arl::controller::GravityCompensation:

Public Member Functions
	GravityCompensation (const std::shared_ptr< arl::robot::Robot > &robot)
Public Member Functions inherited from arl::robot::Controller
	Controller (std::shared_ptr< Robot > r, const std::string &name, Timing timing=FIXED)
	Constructor which initializes the robot controller. More...
	~Controller ()
bool	run ()
	The main function that runs the controller. More...
bool	runRT ()
	Runs the controller with real time priority. More...
void	setExternalStop (bool arg)
	Sets an external stop to the controller. Another external thread can use this function to stop the controller. More...
std::string	getName ()
	Returns the name of the controller. More...
double	getTime () const
	Returns the current time since the start of the controller in seconds. More...
virtual void	enableLogging (const std::string &log_path="/home/user/autharl_logfiles/")
	Enables the logging by opening files for log benchmarking times and data. More...
virtual void	reference (const arma::mat &ref)

Protected Member Functions
void	init ()
	Initializes the controller. More...
void	update ()
	Performs the necessary calculations of the controller. More...
void	command ()
	Commands the robot. More...
bool	stop ()
	Implements the stopping condition of your controller. More...
Protected Member Functions inherited from arl::robot::Controller
virtual bool	success ()
	Implements the success condition of your controller. More...
virtual void	measure ()
	Measures the desired data. More...
virtual void	waitNextCycle ()
	Sets a new reference for the controller. More...

Additional Inherited Members
Public Types inherited from arl::robot::Controller
enum	Timing { FIXED, DYNAMIC }
Protected Attributes inherited from arl::robot::Controller
std::string	name
	The name of the controller. More...
bool	external_stop
	The external stopped setted by Controller::setExternalStop() More...
std::shared_ptr< Robot >	robot
	The pointer to the robot to be controlled. More...
double	t
	The current time t, with t = 0 when the controller is created. Alternatively the user can initialize time durint the init() function of its derived controller. More...
double	dt
	The cycle time of the control loop, obtained by the robot. More...
bool	stop_flag_
utils::Timer	timer
	Used for measuring the current time of the controller. More...
utils::Timer	benchmark_total_timer_
utils::Timer	benchmark_timer_
io::Logger	benchmark_logger_
io::Logger	logger_
Timing	timing_

Detailed Description

Implements a gravity compensation controller.

This controller commands all of the joints of the robot with zero torques.

Attention

It assumes that the robot in use is torque controlled.

Example of use:

#include <autharl_core/controllers/gravity_compensation.h>
#include <lwr_robot/robot/robot.h>
// ...
// Use the KUKA LWR4+
auto model  = std::make_shared<lwr::robot::Model>("/robot_description");
auto robot  = std::make_shared<lwr::robot::Robot>(model);
GravityCompensation controller(robot);
controller.run();

Constructor & Destructor Documentation

arl::controller::GravityCompensation::GravityCompensation ( const std::shared_ptr< arl::robot::Robot > &  robot )

explicit

Member Function Documentation

void arl::controller::GravityCompensation::command ( )

protectedvirtual

Commands the robot.

Implemented according to your controller needs. Basically makes calls to functions of the Robot class, like sending new desired joint torques or joint positions. These desired signals can be stored in internal variables and should have been calculated based on the measurements of the Controller::measure() and the calculations of the Controller::update()

Reimplemented from arl::robot::Controller.

void arl::controller::GravityCompensation::init ( )

protectedvirtual

Initializes the controller.

Implemented according to your controller needs. Common use cases involve sending a the robot in an initial configuration, setting the robot mode (to position or torque control) or setting the paramters and gains of your controller.

Reimplemented from arl::robot::Controller.

bool arl::controller::GravityCompensation::stop ( )

protectedvirtual

Implements the stopping condition of your controller.

Implemented according to your controller needs. Common use cases involve stopping conditions like your robot has zero velocity, the robot hardware signals an error or dangerous movements indicates the immediate stop.

Returns

True if the controller should stop. False otherwise.

Reimplemented from arl::robot::Controller.

void arl::controller::GravityCompensation::update ( )

protectedvirtual

Performs the necessary calculations of the controller.

Implemented according to your controller needs. The calculations can use the measurements from the Controller::measure() which is stored in internal variables and store the results for the Controller::command() to use.

Implements arl::robot::Controller.