The SteeringKinematics class handles forward kinematics (odometry calculations) and inverse kinematics (getting commands) (2D pose and velocity with related timestamp) More...

#include <steering_kinematics.hpp>

Public Member Functions
	SteeringKinematics (size_t velocity_rolling_window_size=10)
	Constructor Timestamp will get the current time value Value will be set to zero.

void	init (const rclcpp::Time &time)
	Initialize the SteeringKinematics class.

bool	update_from_position (const double traction_wheel_pos, const double steer_pos, const double dt)
	Updates the SteeringKinematics class with latest wheels position.

bool	update_from_position (const double right_traction_wheel_pos, const double left_traction_wheel_pos, const double steer_pos, const double dt)
	Updates the SteeringKinematics class with latest wheels position.

bool	update_from_position (const double right_traction_wheel_pos, const double left_traction_wheel_pos, const double right_steer_pos, const double left_steer_pos, const double dt)
	Updates the SteeringKinematics class with latest wheels position.

bool	update_from_velocity (const double traction_wheel_vel, const double steer_pos, const double dt)
	Updates the SteeringKinematics class with latest wheels position.

bool	update_from_velocity (const double right_traction_wheel_vel, const double left_traction_wheel_vel, const double steer_pos, const double dt)
	Updates the SteeringKinematics class with latest wheels position.

bool	update_from_velocity (const double right_traction_wheel_vel, const double left_traction_wheel_vel, const double right_steer_pos, const double left_steer_pos, const double dt)
	Updates the SteeringKinematics class with latest wheels position.

void	update_open_loop (const double v_bx, const double omega_bz, const double dt)
	Updates the SteeringKinematics class with latest velocity command.

void	set_odometry_type (const unsigned int type)
	Set odometry type.

unsigned int	get_odometry_type () const
	Get odometry type.

double	get_heading () const
	heading getter

double	get_x () const
	x position getter

double	get_y () const
	y position getter

double	get_linear () const
	linear velocity getter

double	get_angular () const
	angular velocity getter

void	set_wheel_params (const double wheel_radius, const double wheel_base=0.0, const double wheel_track=0.0)
	Sets the wheel parameters: radius, wheel_base, and wheel_track.

void	set_wheel_params (const double wheel_radius, const double wheel_base, const double wheel_track_steering, const double wheel_track_traction)
	Sets the wheel parameters: radius, wheel_base, and wheel_track for steering and traction.

void	set_velocity_rolling_window_size (const size_t velocity_rolling_window_size)
	Velocity rolling window size setter.

std::tuple< std::vector< double >, std::vector< double > >	get_commands (const double v_bx, const double omega_bz, const bool open_loop=true, const bool reduce_wheel_speed_until_steering_reached=false)
	Calculates inverse kinematics for the desired linear and angular velocities.

void	reset_odometry ()
	Reset poses, heading, and accumulators.

void	set_odometry (const double &x, const double &y, const double &heading)
	Set poses and heading with the given values and reset accumulators.

Detailed Description

The SteeringKinematics class handles forward kinematics (odometry calculations) and inverse kinematics (getting commands) (2D pose and velocity with related timestamp)

Constructor & Destructor Documentation

◆ SteeringKinematics()

steering_kinematics::SteeringKinematics::SteeringKinematics ( size_t velocity_rolling_window_size = 10 )

explicit

Constructor Timestamp will get the current time value Value will be set to zero.

Parameters

velocity_rolling_window_size Rolling window size used to compute the velocity mean

Member Function Documentation

◆ get_angular()

double steering_kinematics::SteeringKinematics::get_angular ( ) const

inline

angular velocity getter

Returns: angular velocity [rad/s]

◆ get_commands()

std::tuple< std::vector< double >, std::vector< double > > steering_kinematics::SteeringKinematics::get_commands	(	const double	v_bx,
		const double	omega_bz,
		const bool	open_loop = `true`,
		const bool	reduce_wheel_speed_until_steering_reached = `false`
	)

Calculates inverse kinematics for the desired linear and angular velocities.

Parameters

v_bx	Desired linear velocity of the robot in x_b-axis direction
omega_bz	Desired angular velocity of the robot around x_z-axis
open_loop	If false, the IK will be calculated using measured steering angle
reduce_wheel_speed_until_steering_reached	Reduce wheel speed until the steering angle has been reached

Returns: Tuple of velocity commands and steering commands

◆ get_heading()

double steering_kinematics::SteeringKinematics::get_heading ( ) const

inline

heading getter

Returns: heading [rad]

◆ get_linear()

double steering_kinematics::SteeringKinematics::get_linear ( ) const

inline

linear velocity getter

Returns: linear velocity [m/s]

◆ get_odometry_type()

unsigned int steering_kinematics::SteeringKinematics::get_odometry_type ( ) const

inline

Get odometry type.

Returns: odometry type

◆ get_x()

double steering_kinematics::SteeringKinematics::get_x ( ) const

inline

x position getter

Returns: x position [m]

◆ get_y()

double steering_kinematics::SteeringKinematics::get_y ( ) const

inline

y position getter

Returns: y position [m]

◆ init()

void steering_kinematics::SteeringKinematics::init ( const rclcpp::Time & time )

Initialize the SteeringKinematics class.

Parameters

time	Current time

◆ set_odometry()

void steering_kinematics::SteeringKinematics::set_odometry	(	const double &	x,
		const double &	y,
		const double &	heading
	)

Set poses and heading with the given values and reset accumulators.

Parameters

x	x position [m]
y	y position [m]
heading	heading [rad]

◆ set_odometry_type()

void steering_kinematics::SteeringKinematics::set_odometry_type ( const unsigned int type )

Set odometry type.

Parameters

type	odometry type

◆ set_velocity_rolling_window_size()

void steering_kinematics::SteeringKinematics::set_velocity_rolling_window_size ( const size_t velocity_rolling_window_size )

Velocity rolling window size setter.

Parameters

velocity_rolling_window_size Velocity rolling window size

◆ update_from_position() [1/3]

bool steering_kinematics::SteeringKinematics::update_from_position	(	const double	right_traction_wheel_pos,
		const double	left_traction_wheel_pos,
		const double	right_steer_pos,
		const double	left_steer_pos,
		const double	dt
	)

Updates the SteeringKinematics class with latest wheels position.

Parameters

right_traction_wheel_pos	Right traction wheel position [rad]
left_traction_wheel_pos	Left traction wheel position [rad]
right_steer_pos	Right steer wheel position [rad]
left_steer_pos	Left steer wheel position [rad]
dt	time difference to last call

Returns: true if the odometry is actually updated

Update old position with current:

◆ update_from_position() [2/3]

bool steering_kinematics::SteeringKinematics::update_from_position	(	const double	right_traction_wheel_pos,
		const double	left_traction_wheel_pos,
		const double	steer_pos,
		const double	dt
	)

Updates the SteeringKinematics class with latest wheels position.

Parameters

right_traction_wheel_pos	Right traction wheel velocity [rad]
left_traction_wheel_pos	Left traction wheel velocity [rad]
steer_pos	Steer wheel position [rad]
dt	time difference to last call

Returns: true if the odometry is actually updated

Update old position with current:

◆ update_from_position() [3/3]

bool steering_kinematics::SteeringKinematics::update_from_position	(	const double	traction_wheel_pos,
		const double	steer_pos,
		const double	dt
	)

Updates the SteeringKinematics class with latest wheels position.

Parameters

traction_wheel_pos	traction wheel position [rad]
steer_pos	Steer wheel position [rad]
dt	time difference to last call

Returns: true if the odometry is actually updated

Update old position with current:

◆ update_from_velocity() [1/3]

bool steering_kinematics::SteeringKinematics::update_from_velocity	(	const double	right_traction_wheel_vel,
		const double	left_traction_wheel_vel,
		const double	right_steer_pos,
		const double	left_steer_pos,
		const double	dt
	)

Updates the SteeringKinematics class with latest wheels position.

Parameters

right_traction_wheel_vel	Right traction wheel velocity [rad/s]
left_traction_wheel_vel	Left traction wheel velocity [rad/s]
right_steer_pos	Right steer wheel position [rad]
left_steer_pos	Left steer wheel position [rad]
dt	time difference to last call

Returns: true if the odometry is actually updated

◆ update_from_velocity() [2/3]

bool steering_kinematics::SteeringKinematics::update_from_velocity	(	const double	right_traction_wheel_vel,
		const double	left_traction_wheel_vel,
		const double	steer_pos,
		const double	dt
	)

Updates the SteeringKinematics class with latest wheels position.

Parameters

right_traction_wheel_vel	Right traction wheel velocity [rad/s]
left_traction_wheel_vel	Left traction wheel velocity [rad/s]
steer_pos	Steer wheel position [rad]
dt	time difference to last call

Returns: true if the odometry is actually updated

◆ update_from_velocity() [3/3]

bool steering_kinematics::SteeringKinematics::update_from_velocity	(	const double	traction_wheel_vel,
		const double	steer_pos,
		const double	dt
	)

Updates the SteeringKinematics class with latest wheels position.

Parameters

traction_wheel_vel	Traction wheel velocity [rad/s]
steer_pos	Steer wheel position [rad]
dt	time difference to last call

Returns: true if the odometry is actually updated

◆ update_open_loop()

void steering_kinematics::SteeringKinematics::update_open_loop	(	const double	v_bx,
		const double	omega_bz,
		const double	dt
	)

Updates the SteeringKinematics class with latest velocity command.

Parameters

v_bx	Linear velocity [m/s]
omega_bz	Angular velocity [rad/s]
dt	time difference to last call

Save last linear and angular velocity:

Integrate odometry:

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

ros2_controllers/steering_controllers_library/include/steering_controllers_library/steering_kinematics.hpp
ros2_controllers/steering_controllers_library/src/steering_kinematics.cpp

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ SteeringKinematics()

Member Function Documentation

◆ get_angular()

◆ get_commands()

◆ get_heading()

◆ get_linear()

◆ get_odometry_type()

◆ get_x()

◆ get_y()

◆ init()

◆ set_odometry()

◆ set_odometry_type()

◆ set_velocity_rolling_window_size()

◆ update_from_position() [1/3]

◆ update_from_position() [2/3]

◆ update_from_position() [3/3]

◆ update_from_velocity() [1/3]

◆ update_from_velocity() [2/3]

◆ update_from_velocity() [3/3]

◆ update_open_loop()