#include <mecanum_drive_controller.h>

Inheritance diagram for mecanum_drive_controller::MecanumDriveController:

Classes
struct	Commands
	Velocity command related: More...
Public Member Functions
bool	init (hardware_interface::VelocityJointInterface *hw, ros::NodeHandle &root_nh, ros::NodeHandle &controller_nh)
	Initialize controller.
	MecanumDriveController ()
void	starting (const ros::Time &time)
	Starts controller.
void	stopping (const ros::Time &time)
	Stops controller.
void	update (const ros::Time &time, const ros::Duration &period)
	Updates controller, i.e. computes the odometry and sets the new velocity commands.
Private Member Functions
void	brake ()
	Brakes the wheels, i.e. sets the velocity to 0.
void	cmdVelCallback (const geometry_msgs::Twist &command)
	Velocity command callback.
bool	getWheelRadius (const boost::shared_ptr< urdf::ModelInterface > model, const boost::shared_ptr< const urdf::Link > &wheel_link, double &wheel_radius)
	Get the radius of a given wheel.
void	setupRtPublishersMsg (ros::NodeHandle &root_nh, ros::NodeHandle &controller_nh)
	Sets the odometry publishing fields.
bool	setWheelParamsFromUrdf (ros::NodeHandle &root_nh, ros::NodeHandle &controller_nh, const std::string &wheel0_name, const std::string &wheel1_name, const std::string &wheel2_name, const std::string &wheel3_name)
	Sets odometry parameters from the URDF, i.e. the wheel radius and separation.
Private Attributes
std::string	base_frame_id_
	Frame to use for the robot base:
double	cmd_vel_timeout_
	Timeout to consider cmd_vel commands old:
realtime_tools::RealtimeBuffer < Commands >	command_
Commands	command_struct_
bool	enable_odom_tf_
	Whether to publish odometry to tf or not:
Commands	last_cmd_
ros::Time	last_state_publish_time_
SpeedLimiter	limiter_ang_
SpeedLimiter	limiter_linX_
SpeedLimiter	limiter_linY_
std::string	name_
geometry_msgs::TransformStamped	odom_frame_
boost::shared_ptr < realtime_tools::RealtimePublisher < nav_msgs::Odometry > >	odom_pub_
	Odometry related:
Odometry	odometry_
bool	open_loop_
ros::Duration	publish_period_
	Odometry related:
ros::Subscriber	sub_command_
boost::shared_ptr < realtime_tools::RealtimePublisher < tf::tfMessage > >	tf_odom_pub_
bool	use_realigned_roller_joints_
	Wheel radius (assuming it's the same for the left and right wheels):
hardware_interface::JointHandle	wheel0_jointHandle_
	Hardware handles:
hardware_interface::JointHandle	wheel1_jointHandle_
hardware_interface::JointHandle	wheel2_jointHandle_
hardware_interface::JointHandle	wheel3_jointHandle_
size_t	wheel_joints_size_
	Number of wheel joints:
double	wheel_separation_x_
double	wheel_separation_y_
double	wheels_k_
double	wheels_radius_

Detailed Description

This class makes some assumptions on the model of the robot:

the rotation axes of wheels are collinear
the wheels are identical in radius Additional assumptions to not duplicate information readily available in the URDF:
the wheels have the same parent frame
a wheel collision geometry is a cylinder in the urdf
a wheel joint frame center's vertical projection on the floor must lie within the contact patch

Definition at line 64 of file mecanum_drive_controller.h.

Constructor & Destructor Documentation

mecanum_drive_controller::MecanumDriveController::MecanumDriveController ( )

Definition at line 81 of file mecanum_drive_controller.cpp.

Member Function Documentation

void mecanum_drive_controller::MecanumDriveController::brake ( ) [private]

Brakes the wheels, i.e. sets the velocity to 0.

Definition at line 292 of file mecanum_drive_controller.cpp.

void mecanum_drive_controller::MecanumDriveController::cmdVelCallback ( const geometry_msgs::Twist & command ) [private]

Velocity command callback.

Parameters:

command Velocity command message (twist)

Definition at line 301 of file mecanum_drive_controller.cpp.

bool mecanum_drive_controller::MecanumDriveController::getWheelRadius	(	const boost::shared_ptr< urdf::ModelInterface >	model,
		const boost::shared_ptr< const urdf::Link > &	wheel_link,
		double &	wheel_radius
	)		`[private]`

Get the radius of a given wheel.

Parameters:

	model	urdf model used
	wheel_link	link of the wheel from which to get the radius
[out]	wheels_radius	radius of the wheel read from the urdf

Definition at line 464 of file mecanum_drive_controller.cpp.

bool mecanum_drive_controller::MecanumDriveController::init	(	hardware_interface::VelocityJointInterface *	hw,
		ros::NodeHandle &	root_nh,
		ros::NodeHandle &	controller_nh
	)		`[virtual]`

Initialize controller.

Parameters:

hw	Velocity joint interface for the wheels
root_nh	Node handle at root namespace
controller_nh	Node handle inside the controller namespace

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

Definition at line 96 of file mecanum_drive_controller.cpp.

void mecanum_drive_controller::MecanumDriveController::setupRtPublishersMsg	(	ros::NodeHandle &	root_nh,
		ros::NodeHandle &	controller_nh
	)		`[private]`

Sets the odometry publishing fields.

Parameters:

root_nh	Root node handle
controller_nh	Node handle inside the controller namespace

Definition at line 504 of file mecanum_drive_controller.cpp.

bool mecanum_drive_controller::MecanumDriveController::setWheelParamsFromUrdf	(	ros::NodeHandle &	root_nh,
		ros::NodeHandle &	controller_nh,
		const std::string &	wheel0_name,
		const std::string &	wheel1_name,
		const std::string &	wheel2_name,
		const std::string &	wheel3_name
	)		`[private]`